diff --git a/promql/parser/generated_parser.y b/promql/parser/generated_parser.y
index dce79f769..5f5e2a1d7 100644
--- a/promql/parser/generated_parser.y
+++ b/promql/parser/generated_parser.y
@@ -161,7 +161,7 @@ START_METRIC_SELECTOR
 // Type definitions for grammar rules.
 %type <matchers> label_match_list
 %type <matcher> label_matcher
-%type <item> aggregate_op grouping_label match_op maybe_label metric_identifier unary_op at_modifier_preprocessors
+%type <item> aggregate_op grouping_label match_op maybe_label metric_identifier unary_op at_modifier_preprocessors string_identifier
 %type <labels> label_set metric
 %type <lblList> label_set_list
 %type <label> label_set_item
@@ -582,7 +582,11 @@ label_match_list: label_match_list COMMA label_matcher
                 ;
 
 label_matcher   : IDENTIFIER match_op STRING
-                        { $$ = yylex.(*parser).newLabelMatcher($1, $2, $3);  }
+                        { $$ = yylex.(*parser).newLabelMatcher($1, $2, $3); }
+                | string_identifier match_op STRING
+                        { $$ = yylex.(*parser).newLabelMatcher($1, $2, $3); }
+                | string_identifier
+                        { $$ = yylex.(*parser).newMetricNameMatcher($1); }
                 | IDENTIFIER match_op error
                         { yylex.(*parser).unexpected("label matching", "string"); $$ = nil}
                 | IDENTIFIER error
@@ -901,7 +905,17 @@ string_literal  : STRING
                                 PosRange: $1.PositionRange(),
                         }
                         }
-                        ;
+                ;
+
+string_identifier  : STRING
+                        {
+                        $$ = Item{
+                                Typ: METRIC_IDENTIFIER,
+                                Pos: $1.PositionRange().Start,
+                                Val: yylex.(*parser).unquoteString($1.Val),
+                        }
+                        }
+                ;
 
 /*
  * Wrappers for optional arguments.
diff --git a/promql/parser/generated_parser.y.go b/promql/parser/generated_parser.y.go
index 4057d9163..888119a97 100644
--- a/promql/parser/generated_parser.y.go
+++ b/promql/parser/generated_parser.y.go
@@ -1,12 +1,8 @@
-// Code generated by goyacc -o promql/parser/generated_parser.y.go promql/parser/generated_parser.y. DO NOT EDIT.
-
-//line promql/parser/generated_parser.y:15
+// Code generated by goyacc -l -o promql/parser/generated_parser.y.go promql/parser/generated_parser.y. DO NOT EDIT.
 package parser
 
 import __yyfmt__ "fmt"
 
-//line promql/parser/generated_parser.y:15
-
 import (
 	"math"
 	"strconv"
@@ -18,7 +14,6 @@ import (
 	"github.com/prometheus/prometheus/promql/parser/posrange"
 )
 
-//line promql/parser/generated_parser.y:30
 type yySymType struct {
 	yys         int
 	node        Node
@@ -230,312 +225,305 @@ const yyEofCode = 1
 const yyErrCode = 2
 const yyInitialStackSize = 16
 
-//line promql/parser/generated_parser.y:919
-
-//line yacctab:1
-var yyExca = [...]int16{
+var yyExca = [...]int{
 	-1, 1,
 	1, -1,
 	-2, 0,
 	-1, 35,
-	1, 131,
-	10, 131,
-	24, 131,
+	1, 133,
+	10, 133,
+	24, 133,
 	-2, 0,
 	-1, 58,
-	2, 168,
-	15, 168,
-	75, 168,
-	81, 168,
-	-2, 97,
-	-1, 59,
-	2, 169,
-	15, 169,
-	75, 169,
-	81, 169,
-	-2, 98,
-	-1, 60,
 	2, 170,
 	15, 170,
 	75, 170,
 	81, 170,
-	-2, 100,
-	-1, 61,
+	-2, 99,
+	-1, 59,
 	2, 171,
 	15, 171,
 	75, 171,
 	81, 171,
-	-2, 101,
-	-1, 62,
+	-2, 100,
+	-1, 60,
 	2, 172,
 	15, 172,
 	75, 172,
 	81, 172,
 	-2, 102,
-	-1, 63,
+	-1, 61,
 	2, 173,
 	15, 173,
 	75, 173,
 	81, 173,
-	-2, 107,
-	-1, 64,
+	-2, 103,
+	-1, 62,
 	2, 174,
 	15, 174,
 	75, 174,
 	81, 174,
-	-2, 109,
-	-1, 65,
+	-2, 104,
+	-1, 63,
 	2, 175,
 	15, 175,
 	75, 175,
 	81, 175,
-	-2, 111,
-	-1, 66,
+	-2, 109,
+	-1, 64,
 	2, 176,
 	15, 176,
 	75, 176,
 	81, 176,
-	-2, 112,
-	-1, 67,
+	-2, 111,
+	-1, 65,
 	2, 177,
 	15, 177,
 	75, 177,
 	81, 177,
 	-2, 113,
-	-1, 68,
+	-1, 66,
 	2, 178,
 	15, 178,
 	75, 178,
 	81, 178,
 	-2, 114,
-	-1, 69,
+	-1, 67,
 	2, 179,
 	15, 179,
 	75, 179,
 	81, 179,
 	-2, 115,
-	-1, 192,
-	12, 226,
-	13, 226,
-	18, 226,
-	19, 226,
-	25, 226,
-	39, 226,
-	45, 226,
-	46, 226,
-	49, 226,
-	55, 226,
-	60, 226,
-	61, 226,
-	62, 226,
-	63, 226,
-	64, 226,
-	65, 226,
-	66, 226,
-	67, 226,
-	68, 226,
-	69, 226,
-	70, 226,
-	71, 226,
-	75, 226,
-	79, 226,
-	81, 226,
-	84, 226,
-	85, 226,
+	-1, 68,
+	2, 180,
+	15, 180,
+	75, 180,
+	81, 180,
+	-2, 116,
+	-1, 69,
+	2, 181,
+	15, 181,
+	75, 181,
+	81, 181,
+	-2, 117,
+	-1, 195,
+	12, 229,
+	13, 229,
+	18, 229,
+	19, 229,
+	25, 229,
+	39, 229,
+	45, 229,
+	46, 229,
+	49, 229,
+	55, 229,
+	60, 229,
+	61, 229,
+	62, 229,
+	63, 229,
+	64, 229,
+	65, 229,
+	66, 229,
+	67, 229,
+	68, 229,
+	69, 229,
+	70, 229,
+	71, 229,
+	75, 229,
+	79, 229,
+	81, 229,
+	84, 229,
+	85, 229,
 	-2, 0,
-	-1, 193,
-	12, 226,
-	13, 226,
-	18, 226,
-	19, 226,
-	25, 226,
-	39, 226,
-	45, 226,
-	46, 226,
-	49, 226,
-	55, 226,
-	60, 226,
-	61, 226,
-	62, 226,
-	63, 226,
-	64, 226,
-	65, 226,
-	66, 226,
-	67, 226,
-	68, 226,
-	69, 226,
-	70, 226,
-	71, 226,
-	75, 226,
-	79, 226,
-	81, 226,
-	84, 226,
-	85, 226,
+	-1, 196,
+	12, 229,
+	13, 229,
+	18, 229,
+	19, 229,
+	25, 229,
+	39, 229,
+	45, 229,
+	46, 229,
+	49, 229,
+	55, 229,
+	60, 229,
+	61, 229,
+	62, 229,
+	63, 229,
+	64, 229,
+	65, 229,
+	66, 229,
+	67, 229,
+	68, 229,
+	69, 229,
+	70, 229,
+	71, 229,
+	75, 229,
+	79, 229,
+	81, 229,
+	84, 229,
+	85, 229,
 	-2, 0,
-	-1, 214,
-	21, 224,
+	-1, 217,
+	21, 227,
 	-2, 0,
-	-1, 280,
-	21, 225,
+	-1, 284,
+	21, 228,
 	-2, 0,
 }
 
 const yyPrivate = 57344
 
-const yyLast = 756
+const yyLast = 697
 
-var yyAct = [...]int16{
-	149, 317, 315, 263, 322, 146, 218, 184, 37, 142,
-	275, 276, 150, 113, 77, 101, 220, 102, 6, 104,
-	148, 190, 103, 191, 126, 105, 230, 192, 193, 153,
-	287, 334, 236, 312, 311, 106, 308, 153, 257, 255,
-	249, 289, 153, 254, 335, 121, 172, 144, 173, 154,
-	333, 258, 154, 332, 145, 248, 278, 154, 306, 232,
-	233, 153, 108, 234, 109, 155, 316, 259, 155, 107,
-	287, 247, 296, 155, 221, 223, 225, 226, 227, 235,
-	237, 240, 241, 242, 243, 244, 175, 100, 222, 224,
-	228, 229, 231, 238, 239, 104, 174, 176, 245, 246,
-	143, 105, 151, 152, 2, 3, 4, 5, 188, 57,
-	156, 295, 82, 84, 210, 166, 160, 163, 159, 158,
-	106, 323, 186, 93, 94, 100, 294, 96, 97, 99,
-	83, 189, 178, 293, 187, 100, 194, 195, 196, 197,
+var yyAct = [...]int{
+	151, 321, 319, 267, 326, 148, 221, 187, 144, 37,
+	113, 279, 280, 152, 173, 77, 101, 223, 102, 6,
+	104, 150, 193, 103, 194, 128, 105, 233, 195, 196,
+	155, 291, 338, 239, 316, 146, 106, 312, 155, 261,
+	259, 257, 147, 155, 57, 339, 315, 174, 293, 175,
+	156, 337, 262, 156, 336, 258, 123, 282, 156, 310,
+	235, 236, 155, 108, 237, 109, 157, 320, 263, 157,
+	107, 100, 250, 291, 157, 224, 226, 228, 229, 230,
+	238, 240, 243, 244, 245, 246, 247, 177, 145, 225,
+	227, 231, 232, 234, 241, 242, 104, 176, 178, 248,
+	249, 110, 105, 153, 154, 2, 3, 4, 5, 158,
+	256, 96, 223, 99, 252, 183, 168, 162, 165, 161,
+	160, 300, 233, 327, 189, 124, 147, 191, 239, 251,
+	179, 213, 220, 255, 192, 181, 98, 190, 182, 197,
 	198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
-	208, 84, 98, 209, 220, 211, 212, 122, 253, 180,
-	72, 93, 94, 33, 230, 96, 110, 99, 83, 215,
-	236, 284, 162, 214, 217, 96, 283, 99, 7, 281,
-	145, 252, 179, 251, 10, 161, 145, 170, 213, 115,
-	98, 282, 169, 307, 74, 305, 256, 232, 233, 114,
-	98, 234, 273, 274, 277, 168, 304, 250, 303, 247,
-	302, 301, 221, 223, 225, 226, 227, 235, 237, 240,
-	241, 242, 243, 244, 280, 300, 222, 224, 228, 229,
-	231, 238, 239, 157, 299, 298, 245, 246, 297, 81,
-	145, 127, 128, 129, 130, 131, 132, 133, 134, 135,
-	136, 137, 138, 139, 140, 141, 286, 288, 285, 290,
-	79, 182, 120, 34, 119, 48, 291, 292, 185, 262,
-	78, 73, 188, 8, 118, 153, 261, 35, 177, 117,
-	265, 266, 264, 270, 272, 269, 271, 267, 268, 115,
-	309, 310, 116, 1, 279, 154, 47, 314, 46, 114,
-	319, 320, 321, 45, 318, 44, 324, 112, 326, 325,
-	79, 155, 125, 327, 328, 43, 51, 72, 329, 53,
-	78, 42, 22, 52, 331, 41, 165, 56, 76, 54,
-	9, 9, 123, 336, 164, 40, 124, 39, 38, 49,
-	183, 330, 260, 70, 80, 181, 216, 75, 147, 18,
-	19, 55, 219, 20, 171, 50, 111, 0, 0, 71,
-	0, 0, 0, 0, 58, 59, 60, 61, 62, 63,
-	64, 65, 66, 67, 68, 69, 0, 0, 0, 13,
+	208, 209, 210, 211, 212, 235, 236, 214, 215, 237,
+	106, 72, 33, 7, 309, 308, 307, 250, 306, 305,
+	224, 226, 228, 229, 230, 238, 240, 243, 244, 245,
+	246, 247, 254, 299, 225, 227, 231, 232, 234, 241,
+	242, 164, 285, 304, 248, 249, 311, 303, 298, 147,
+	260, 302, 100, 175, 163, 297, 277, 278, 281, 129,
+	130, 131, 132, 133, 134, 135, 136, 137, 138, 139,
+	140, 141, 142, 143, 301, 81, 284, 82, 84, 85,
+	34, 86, 87, 88, 89, 90, 91, 92, 93, 94,
+	95, 177, 96, 97, 99, 83, 116, 1, 288, 100,
+	283, 176, 178, 287, 218, 10, 114, 169, 217, 159,
+	290, 292, 289, 294, 253, 74, 147, 98, 286, 117,
+	295, 296, 47, 216, 82, 84, 85, 46, 86, 87,
+	88, 89, 90, 91, 92, 93, 94, 95, 45, 96,
+	97, 99, 83, 116, 313, 314, 48, 79, 122, 100,
+	121, 318, 73, 114, 323, 324, 325, 78, 322, 44,
+	328, 112, 330, 329, 98, 180, 117, 331, 332, 100,
+	51, 72, 333, 53, 82, 84, 22, 52, 335, 127,
+	167, 43, 42, 54, 79, 93, 94, 340, 41, 96,
+	97, 99, 83, 125, 78, 84, 56, 70, 166, 9,
+	9, 40, 76, 18, 19, 93, 94, 20, 126, 96,
+	39, 99, 83, 71, 98, 38, 49, 186, 58, 59,
+	60, 61, 62, 63, 64, 65, 66, 67, 68, 69,
+	172, 334, 8, 13, 98, 171, 35, 24, 264, 30,
+	120, 80, 31, 32, 36, 119, 51, 72, 170, 53,
+	184, 219, 22, 52, 75, 115, 185, 149, 118, 54,
+	55, 222, 50, 188, 111, 0, 0, 191, 0, 0,
+	155, 0, 0, 70, 0, 0, 0, 0, 0, 18,
+	19, 0, 0, 20, 0, 0, 0, 0, 0, 71,
+	156, 0, 0, 0, 58, 59, 60, 61, 62, 63,
+	64, 65, 66, 67, 68, 69, 157, 0, 0, 13,
 	0, 0, 0, 24, 0, 30, 0, 0, 31, 32,
-	36, 0, 51, 72, 0, 53, 313, 0, 22, 52,
-	0, 0, 0, 0, 0, 54, 0, 265, 266, 264,
-	270, 272, 269, 271, 267, 268, 0, 0, 0, 70,
-	0, 0, 0, 0, 0, 18, 19, 0, 0, 20,
-	0, 0, 0, 0, 0, 71, 0, 0, 0, 0,
-	58, 59, 60, 61, 62, 63, 64, 65, 66, 67,
-	68, 69, 0, 0, 0, 13, 0, 0, 0, 24,
-	0, 30, 0, 0, 31, 32, 51, 72, 0, 53,
-	0, 0, 22, 52, 0, 0, 0, 0, 0, 54,
+	51, 72, 0, 53, 266, 0, 22, 52, 0, 0,
+	0, 265, 0, 54, 0, 269, 270, 268, 274, 276,
+	273, 275, 271, 272, 0, 0, 0, 70, 0, 0,
+	0, 0, 0, 18, 19, 0, 0, 20, 0, 0,
+	0, 17, 72, 71, 0, 0, 0, 22, 58, 59,
+	60, 61, 62, 63, 64, 65, 66, 67, 68, 69,
+	0, 0, 0, 13, 0, 0, 0, 24, 0, 30,
+	0, 0, 31, 32, 18, 19, 0, 0, 20, 0,
+	0, 0, 17, 33, 0, 0, 0, 0, 22, 11,
+	12, 14, 15, 16, 21, 23, 25, 26, 27, 28,
+	29, 0, 0, 0, 13, 0, 0, 0, 24, 317,
+	30, 0, 0, 31, 32, 18, 19, 0, 0, 20,
+	269, 270, 268, 274, 276, 273, 275, 271, 272, 0,
+	11, 12, 14, 15, 16, 21, 23, 25, 26, 27,
+	28, 29, 100, 0, 0, 13, 0, 0, 0, 24,
+	0, 30, 0, 0, 31, 32, 0, 0, 0, 0,
+	0, 100, 0, 0, 0, 0, 0, 82, 84, 85,
+	0, 86, 87, 88, 0, 90, 91, 92, 93, 94,
+	95, 0, 96, 97, 99, 83, 82, 84, 85, 0,
+	86, 87, 0, 0, 90, 91, 0, 93, 94, 95,
+	0, 96, 97, 99, 83, 0, 0, 98, 0, 0,
 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 70, 0, 0, 0, 0, 0, 18,
-	19, 0, 0, 20, 0, 0, 0, 17, 72, 71,
-	0, 0, 0, 22, 58, 59, 60, 61, 62, 63,
-	64, 65, 66, 67, 68, 69, 0, 0, 0, 13,
-	0, 0, 0, 24, 0, 30, 0, 0, 31, 32,
-	18, 19, 0, 0, 20, 0, 0, 0, 17, 33,
-	0, 0, 0, 0, 22, 11, 12, 14, 15, 16,
-	21, 23, 25, 26, 27, 28, 29, 0, 0, 0,
-	13, 0, 0, 0, 24, 0, 30, 0, 0, 31,
-	32, 18, 19, 0, 0, 20, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 11, 12, 14, 15,
-	16, 21, 23, 25, 26, 27, 28, 29, 100, 0,
-	0, 13, 0, 0, 0, 24, 167, 30, 0, 0,
-	31, 32, 0, 0, 0, 0, 0, 100, 0, 0,
-	0, 0, 0, 82, 84, 85, 0, 86, 87, 88,
-	89, 90, 91, 92, 93, 94, 95, 0, 96, 97,
-	99, 83, 82, 84, 85, 0, 86, 87, 88, 89,
-	90, 91, 92, 93, 94, 95, 0, 96, 97, 99,
-	83, 100, 0, 98, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	100, 0, 98, 0, 0, 0, 82, 84, 85, 0,
-	86, 87, 88, 0, 90, 91, 92, 93, 94, 95,
-	0, 96, 97, 99, 83, 82, 84, 85, 0, 86,
-	87, 0, 0, 90, 91, 0, 93, 94, 95, 0,
-	96, 97, 99, 83, 0, 0, 98, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 0, 0, 98,
+	0, 0, 0, 0, 0, 0, 98,
 }
 
-var yyPact = [...]int16{
-	16, 168, 536, 536, 380, 495, -1000, -1000, -1000, 150,
+var yyPact = [...]int{
+	17, 153, 540, 540, 384, 499, -1000, -1000, -1000, 149,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
-	-1000, -1000, -1000, 308, -1000, 237, -1000, 613, -1000, -1000,
+	-1000, -1000, -1000, 332, -1000, 223, -1000, 188, -1000, -1000,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
-	20, 105, -1000, 454, -1000, 454, 147, -1000, -1000, -1000,
+	21, 145, -1000, 458, -1000, 458, 148, -1000, -1000, -1000,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
-	-1000, -1000, 287, -1000, -1000, 272, -1000, -1000, 260, -1000,
-	21, -1000, -50, -50, -50, -50, -50, -50, -50, -50,
-	-50, -50, -50, -50, -50, -50, -50, -50, 45, 18,
-	231, 105, -56, -1000, 170, 170, 304, -1000, 594, 121,
-	-1000, 185, -1000, -1000, 44, -1000, -1000, 258, -1000, 157,
-	-1000, 256, 454, -1000, -57, -49, -1000, 454, 454, 454,
-	454, 454, 454, 454, 454, 454, 454, 454, 454, 454,
-	454, 454, -1000, 171, -1000, -1000, -1000, 99, -1000, -1000,
-	-1000, -1000, -1000, -1000, 42, 42, 167, -1000, -1000, -1000,
-	-1000, 152, -1000, -1000, 33, -1000, 613, -1000, -1000, 187,
-	-1000, 156, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
-	-1000, -1000, 17, 13, 12, -1000, -1000, -1000, 252, 111,
-	170, 170, 170, 170, 121, 121, 73, 73, 73, 676,
-	657, 73, 73, 676, 121, 121, 73, 121, 111, -1000,
-	34, -1000, -1000, -1000, 177, -1000, 169, -1000, -1000, -1000,
+	-1000, -1000, 291, -1000, -1000, 388, -1000, -1000, 296, -1000,
+	32, -1000, -49, -49, -49, -49, -49, -49, -49, -49,
+	-49, -49, -49, -49, -49, -49, -49, -49, 33, 19,
+	257, 145, -55, -1000, 189, 189, 308, -1000, 235, 57,
+	-1000, 378, -1000, -1000, 45, 199, -1000, -1000, -1000, 295,
+	-1000, 113, -1000, 401, 458, -1000, -56, -48, -1000, 458,
+	458, 458, 458, 458, 458, 458, 458, 458, 458, 458,
+	458, 458, 458, 458, -1000, 117, -1000, -1000, -1000, 116,
+	-1000, -1000, -1000, -1000, -1000, -1000, 43, 43, 252, -1000,
+	-1000, -1000, -1000, 110, -1000, -1000, 107, -1000, 188, -1000,
+	-1000, 244, -1000, 108, -1000, -1000, -1000, -1000, -1000, 16,
+	-1000, -1000, -1000, -1000, -1000, 29, 14, 13, -1000, -1000,
+	-1000, 457, 305, 189, 189, 189, 189, 57, 57, 285,
+	285, 285, 617, 598, 285, 285, 617, 57, 57, 285,
+	57, 305, -1000, 35, -1000, -1000, -1000, 190, -1000, 246,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
 	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
-	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, 454,
-	-1000, -1000, -1000, -1000, 51, 51, 15, 51, 92, 92,
-	109, 55, -1000, -1000, 232, 229, 228, 219, 205, 204,
-	202, 200, 189, -1000, -1000, -1000, -1000, -1000, -1000, 37,
-	191, -1000, -1000, 14, -1000, 613, -1000, -1000, -1000, 51,
-	-1000, 8, 7, 379, -1000, -1000, -1000, 11, 10, 42,
-	42, 42, 107, 11, 107, 11, -1000, -1000, -1000, -1000,
-	-1000, 51, 51, -1000, -1000, -1000, 51, -1000, -1000, -1000,
-	-1000, -1000, -1000, 42, -1000, -1000, -1000, -1000, -1000, -1000,
-	29, -1000, 23, -1000, -1000, -1000, -1000,
+	-1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000, -1000,
+	-1000, -1000, 458, -1000, -1000, -1000, -1000, -1000, 54, 54,
+	22, 54, 111, 111, 181, 104, -1000, -1000, 218, 195,
+	191, 187, 163, 162, 160, 159, 158, -1000, -1000, -1000,
+	-1000, -1000, -1000, 38, 194, -1000, -1000, 15, -1000, 188,
+	-1000, -1000, -1000, 54, -1000, 20, 8, 562, -1000, -1000,
+	-1000, 12, 11, 43, 43, 43, 109, 12, 109, 12,
+	-1000, -1000, -1000, -1000, -1000, 54, 54, -1000, -1000, -1000,
+	54, -1000, -1000, -1000, -1000, -1000, -1000, 43, -1000, -1000,
+	-1000, -1000, -1000, -1000, 30, -1000, 24, -1000, -1000, -1000,
+	-1000,
 }
 
-var yyPgo = [...]int16{
-	0, 356, 13, 355, 6, 354, 352, 327, 351, 348,
-	184, 273, 347, 14, 346, 11, 10, 345, 344, 7,
-	342, 3, 4, 341, 2, 1, 0, 340, 12, 5,
-	339, 338, 15, 157, 337, 336, 8, 335, 334, 17,
-	332, 109, 325, 321, 315, 312, 305, 303, 298, 296,
-	265, 9, 294, 293, 263,
+var yyPgo = [...]int{
+	0, 414, 10, 412, 6, 14, 411, 346, 410, 407,
+	405, 255, 382, 404, 15, 401, 12, 11, 400, 391,
+	7, 388, 3, 4, 381, 2, 1, 0, 367, 13,
+	5, 366, 365, 16, 125, 360, 358, 9, 351, 348,
+	18, 343, 44, 338, 332, 331, 329, 309, 288, 277,
+	272, 296, 8, 250, 247, 230,
 }
 
-var yyR1 = [...]int8{
-	0, 53, 53, 53, 53, 53, 53, 53, 36, 36,
-	36, 36, 36, 36, 36, 36, 36, 36, 36, 36,
-	31, 31, 31, 31, 32, 32, 34, 34, 34, 34,
-	34, 34, 34, 34, 34, 34, 34, 34, 34, 34,
-	34, 34, 33, 35, 35, 45, 45, 40, 40, 40,
-	40, 15, 15, 15, 15, 14, 14, 14, 4, 4,
-	37, 39, 39, 38, 38, 38, 46, 44, 44, 44,
-	30, 30, 30, 9, 9, 42, 48, 48, 48, 48,
-	48, 49, 50, 50, 50, 41, 41, 41, 1, 1,
-	1, 2, 2, 2, 2, 11, 11, 7, 7, 7,
+var yyR1 = [...]int{
+	0, 54, 54, 54, 54, 54, 54, 54, 37, 37,
+	37, 37, 37, 37, 37, 37, 37, 37, 37, 37,
+	32, 32, 32, 32, 33, 33, 35, 35, 35, 35,
+	35, 35, 35, 35, 35, 35, 35, 35, 35, 35,
+	35, 35, 34, 36, 36, 46, 46, 41, 41, 41,
+	41, 16, 16, 16, 16, 15, 15, 15, 4, 4,
+	38, 40, 40, 39, 39, 39, 47, 45, 45, 45,
+	31, 31, 31, 9, 9, 43, 49, 49, 49, 49,
+	49, 50, 51, 51, 51, 42, 42, 42, 1, 1,
+	1, 2, 2, 2, 2, 2, 2, 12, 12, 7,
 	7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
-	7, 7, 7, 7, 7, 7, 7, 7, 7, 10,
-	10, 10, 10, 12, 12, 12, 13, 13, 13, 13,
-	54, 18, 18, 18, 18, 17, 17, 17, 17, 17,
-	17, 17, 17, 17, 27, 27, 27, 19, 19, 19,
-	19, 20, 20, 20, 21, 21, 21, 21, 21, 21,
-	21, 21, 21, 22, 22, 23, 23, 23, 3, 3,
+	7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
+	7, 11, 11, 11, 11, 13, 13, 13, 14, 14,
+	14, 14, 55, 19, 19, 19, 19, 18, 18, 18,
+	18, 18, 18, 18, 18, 18, 28, 28, 28, 20,
+	20, 20, 20, 21, 21, 21, 22, 22, 22, 22,
+	22, 22, 22, 22, 22, 23, 23, 24, 24, 24,
 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
+	3, 3, 6, 6, 6, 6, 6, 6, 6, 6,
 	6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-	6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
-	6, 6, 6, 6, 6, 6, 6, 8, 8, 5,
-	5, 5, 5, 43, 26, 28, 28, 29, 29, 25,
-	24, 24, 51, 47, 52, 52, 16, 16,
+	6, 6, 6, 6, 6, 6, 6, 6, 6, 8,
+	8, 5, 5, 5, 5, 44, 27, 29, 29, 30,
+	30, 26, 25, 25, 52, 48, 10, 53, 53, 17,
+	17,
 }
 
-var yyR2 = [...]int8{
+var yyR2 = [...]int{
 	0, 2, 2, 2, 2, 2, 2, 1, 1, 1,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 	3, 3, 2, 2, 2, 2, 4, 4, 4, 4,
@@ -545,101 +533,104 @@ var yyR2 = [...]int8{
 	2, 3, 2, 3, 1, 2, 3, 3, 4, 3,
 	3, 5, 3, 1, 1, 4, 6, 6, 5, 4,
 	3, 2, 2, 1, 1, 3, 4, 2, 3, 1,
-	2, 3, 3, 2, 1, 2, 1, 1, 1, 1,
+	2, 3, 3, 1, 3, 2, 1, 2, 1, 1,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 1, 1, 1, 1, 3,
-	4, 2, 0, 3, 1, 2, 3, 3, 2, 1,
-	2, 0, 3, 2, 1, 1, 3, 1, 3, 4,
-	1, 3, 5, 5, 1, 1, 1, 4, 3, 3,
-	2, 3, 1, 2, 3, 3, 3, 3, 3, 3,
-	3, 3, 3, 4, 3, 3, 1, 2, 1, 1,
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+	1, 3, 4, 2, 0, 3, 1, 2, 3, 3,
+	2, 1, 2, 0, 3, 2, 1, 1, 3, 1,
+	3, 4, 1, 3, 5, 5, 1, 1, 1, 4,
+	3, 3, 2, 3, 1, 2, 3, 3, 3, 3,
+	3, 3, 3, 3, 3, 4, 3, 3, 1, 2,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-	1, 1, 1, 1, 1, 2, 2, 1, 1, 1,
-	2, 1, 1, 1, 0, 1, 0, 1,
-}
-
-var yyChk = [...]int16{
-	-1000, -53, 88, 89, 90, 91, 2, 10, -11, -7,
-	-10, 60, 61, 75, 62, 63, 64, 12, 45, 46,
-	49, 65, 18, 66, 79, 67, 68, 69, 70, 71,
-	81, 84, 85, 13, -54, -11, 10, -36, -31, -34,
-	-37, -42, -43, -44, -46, -47, -48, -49, -50, -30,
-	-3, 12, 19, 15, 25, -8, -7, -41, 60, 61,
-	62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
-	39, 55, 13, -50, -10, -12, 20, -13, 12, 2,
-	-18, 2, 39, 57, 40, 41, 43, 44, 45, 46,
-	47, 48, 49, 50, 51, 52, 54, 55, 79, 56,
-	14, -32, -39, 2, 75, 81, 15, -39, -36, -36,
-	-41, -1, 20, -2, 12, 2, 20, 7, 2, 4,
-	2, 24, -33, -40, -35, -45, 74, -33, -33, -33,
-	-33, -33, -33, -33, -33, -33, -33, -33, -33, -33,
-	-33, -33, -51, 55, 2, 9, -29, -9, 2, -26,
-	-28, 84, 85, 19, 39, 55, -51, 2, -39, -32,
-	-15, 15, 2, -15, -38, 22, -36, 22, 20, 7,
-	2, -5, 2, 4, 52, 42, 53, 20, -13, 25,
-	2, -17, 5, -27, -19, 12, -26, -28, 16, -36,
-	78, 80, 76, 77, -36, -36, -36, -36, -36, -36,
-	-36, -36, -36, -36, -36, -36, -36, -36, -36, -51,
-	15, -26, -26, 21, 6, 2, -14, 22, -4, -6,
-	2, 60, 74, 61, 75, 62, 63, 64, 76, 77,
-	12, 78, 45, 46, 49, 65, 18, 66, 79, 80,
-	67, 68, 69, 70, 71, 84, 85, 57, 22, 7,
-	20, -2, 25, 2, 26, 26, -28, 26, 39, 55,
-	-20, 24, 17, -21, 30, 28, 29, 35, 36, 33,
-	31, 34, 32, -15, -15, -16, -15, -16, 22, -52,
-	-51, 2, 22, 7, 2, -36, -25, 19, -25, 26,
-	-25, -19, -19, 24, 17, 2, 17, 6, 6, 6,
-	6, 6, 6, 6, 6, 6, 21, 2, 22, -4,
-	-25, 26, 26, 17, -21, -24, 55, -25, -29, -26,
-	-26, -26, -22, 14, -24, -22, -24, -25, -25, -25,
-	-23, -26, 24, 21, 2, 21, -26,
-}
-
-var yyDef = [...]int16{
-	0, -2, 122, 122, 0, 0, 7, 6, 1, 122,
-	96, 97, 98, 99, 100, 101, 102, 103, 104, 105,
-	106, 107, 108, 109, 110, 111, 112, 113, 114, 115,
-	116, 117, 118, 0, 2, -2, 3, 4, 8, 9,
-	10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
-	0, 103, 213, 0, 223, 0, 83, 84, -2, -2,
-	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
-	207, 208, 0, 5, 95, 0, 121, 124, 0, 129,
-	130, 134, 43, 43, 43, 43, 43, 43, 43, 43,
-	43, 43, 43, 43, 43, 43, 43, 43, 0, 0,
-	0, 0, 22, 23, 0, 0, 0, 60, 0, 81,
-	82, 0, 87, 89, 0, 94, 119, 0, 125, 0,
-	128, 133, 0, 42, 47, 48, 44, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
-	0, 0, 67, 0, 69, 222, 70, 0, 72, 217,
-	218, 73, 74, 214, 0, 0, 0, 80, 20, 21,
-	24, 0, 54, 25, 0, 62, 64, 66, 85, 0,
-	90, 0, 93, 209, 210, 211, 212, 120, 123, 126,
-	127, 132, 135, 137, 140, 144, 145, 146, 0, 26,
-	0, 0, -2, -2, 27, 28, 29, 30, 31, 32,
-	33, 34, 35, 36, 37, 38, 39, 40, 41, 68,
-	0, 215, 216, 75, -2, 79, 0, 53, 56, 58,
-	59, 180, 181, 182, 183, 184, 185, 186, 187, 188,
-	189, 190, 191, 192, 193, 194, 195, 196, 197, 198,
-	199, 200, 201, 202, 203, 204, 205, 206, 61, 65,
-	86, 88, 91, 92, 0, 0, 0, 0, 0, 0,
-	0, 0, 150, 152, 0, 0, 0, 0, 0, 0,
-	0, 0, 0, 45, 46, 49, 227, 50, 71, 0,
-	-2, 78, 51, 0, 57, 63, 136, 219, 138, 0,
-	141, 0, 0, 0, 148, 153, 149, 0, 0, 0,
-	0, 0, 0, 0, 0, 0, 76, 77, 52, 55,
-	139, 0, 0, 147, 151, 154, 0, 221, 155, 156,
-	157, 158, 159, 0, 160, 161, 162, 142, 143, 220,
-	0, 166, 0, 164, 167, 163, 165,
-}
-
-var yyTok1 = [...]int8{
+	1, 1, 1, 1, 1, 1, 1, 2, 2, 1,
+	1, 1, 2, 1, 1, 1, 1, 0, 1, 0,
 	1,
 }
 
-var yyTok2 = [...]int8{
+var yyChk = [...]int{
+	-1000, -54, 88, 89, 90, 91, 2, 10, -12, -7,
+	-11, 60, 61, 75, 62, 63, 64, 12, 45, 46,
+	49, 65, 18, 66, 79, 67, 68, 69, 70, 71,
+	81, 84, 85, 13, -55, -12, 10, -37, -32, -35,
+	-38, -43, -44, -45, -47, -48, -49, -50, -51, -31,
+	-3, 12, 19, 15, 25, -8, -7, -42, 60, 61,
+	62, 63, 64, 65, 66, 67, 68, 69, 70, 71,
+	39, 55, 13, -51, -11, -13, 20, -14, 12, 2,
+	-19, 2, 39, 57, 40, 41, 43, 44, 45, 46,
+	47, 48, 49, 50, 51, 52, 54, 55, 79, 56,
+	14, -33, -40, 2, 75, 81, 15, -40, -37, -37,
+	-42, -1, 20, -2, 12, -10, 2, 25, 20, 7,
+	2, 4, 2, 24, -34, -41, -36, -46, 74, -34,
+	-34, -34, -34, -34, -34, -34, -34, -34, -34, -34,
+	-34, -34, -34, -34, -52, 55, 2, 9, -30, -9,
+	2, -27, -29, 84, 85, 19, 39, 55, -52, 2,
+	-40, -33, -16, 15, 2, -16, -39, 22, -37, 22,
+	20, 7, 2, -5, 2, 4, 52, 42, 53, -5,
+	20, -14, 25, 2, -18, 5, -28, -20, 12, -27,
+	-29, 16, -37, 78, 80, 76, 77, -37, -37, -37,
+	-37, -37, -37, -37, -37, -37, -37, -37, -37, -37,
+	-37, -37, -52, 15, -27, -27, 21, 6, 2, -15,
+	22, -4, -6, 2, 60, 74, 61, 75, 62, 63,
+	64, 76, 77, 12, 78, 45, 46, 49, 65, 18,
+	66, 79, 80, 67, 68, 69, 70, 71, 84, 85,
+	57, 22, 7, 20, -2, 25, 2, 25, 26, 26,
+	-29, 26, 39, 55, -21, 24, 17, -22, 30, 28,
+	29, 35, 36, 33, 31, 34, 32, -16, -16, -17,
+	-16, -17, 22, -53, -52, 2, 22, 7, 2, -37,
+	-26, 19, -26, 26, -26, -20, -20, 24, 17, 2,
+	17, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+	21, 2, 22, -4, -26, 26, 26, 17, -22, -25,
+	55, -26, -30, -27, -27, -27, -23, 14, -25, -23,
+	-25, -26, -26, -26, -24, -27, 24, 21, 2, 21,
+	-27,
+}
+
+var yyDef = [...]int{
+	0, -2, 124, 124, 0, 0, 7, 6, 1, 124,
+	98, 99, 100, 101, 102, 103, 104, 105, 106, 107,
+	108, 109, 110, 111, 112, 113, 114, 115, 116, 117,
+	118, 119, 120, 0, 2, -2, 3, 4, 8, 9,
+	10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
+	0, 105, 215, 0, 225, 0, 83, 84, -2, -2,
+	-2, -2, -2, -2, -2, -2, -2, -2, -2, -2,
+	209, 210, 0, 5, 97, 0, 123, 126, 0, 131,
+	132, 136, 43, 43, 43, 43, 43, 43, 43, 43,
+	43, 43, 43, 43, 43, 43, 43, 43, 0, 0,
+	0, 0, 22, 23, 0, 0, 0, 60, 0, 81,
+	82, 0, 87, 89, 0, 93, 96, 226, 121, 0,
+	127, 0, 130, 135, 0, 42, 47, 48, 44, 0,
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	0, 0, 0, 0, 67, 0, 69, 224, 70, 0,
+	72, 219, 220, 73, 74, 216, 0, 0, 0, 80,
+	20, 21, 24, 0, 54, 25, 0, 62, 64, 66,
+	85, 0, 90, 0, 95, 211, 212, 213, 214, 0,
+	122, 125, 128, 129, 134, 137, 139, 142, 146, 147,
+	148, 0, 26, 0, 0, -2, -2, 27, 28, 29,
+	30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
+	40, 41, 68, 0, 217, 218, 75, -2, 79, 0,
+	53, 56, 58, 59, 182, 183, 184, 185, 186, 187,
+	188, 189, 190, 191, 192, 193, 194, 195, 196, 197,
+	198, 199, 200, 201, 202, 203, 204, 205, 206, 207,
+	208, 61, 65, 86, 88, 91, 94, 92, 0, 0,
+	0, 0, 0, 0, 0, 0, 152, 154, 0, 0,
+	0, 0, 0, 0, 0, 0, 0, 45, 46, 49,
+	230, 50, 71, 0, -2, 78, 51, 0, 57, 63,
+	138, 221, 140, 0, 143, 0, 0, 0, 150, 155,
+	151, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+	76, 77, 52, 55, 141, 0, 0, 149, 153, 156,
+	0, 223, 157, 158, 159, 160, 161, 0, 162, 163,
+	164, 144, 145, 222, 0, 168, 0, 166, 169, 165,
+	167,
+}
+
+var yyTok1 = [...]int{
+	1,
+}
+
+var yyTok2 = [...]int{
 	2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
 	12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
 	22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
@@ -652,7 +643,7 @@ var yyTok2 = [...]int8{
 	92,
 }
 
-var yyTok3 = [...]int8{
+var yyTok3 = [...]int{
 	0,
 }
 
@@ -662,8 +653,6 @@ var yyErrorMessages = [...]struct {
 	msg   string
 }{}
 
-//line yaccpar:1
-
 /*	parser for yacc output	*/
 
 var (
@@ -734,9 +723,9 @@ func yyErrorMessage(state, lookAhead int) string {
 	expected := make([]int, 0, 4)
 
 	// Look for shiftable tokens.
-	base := int(yyPact[state])
+	base := yyPact[state]
 	for tok := TOKSTART; tok-1 < len(yyToknames); tok++ {
-		if n := base + tok; n >= 0 && n < yyLast && int(yyChk[int(yyAct[n])]) == tok {
+		if n := base + tok; n >= 0 && n < yyLast && yyChk[yyAct[n]] == tok {
 			if len(expected) == cap(expected) {
 				return res
 			}
@@ -746,13 +735,13 @@ func yyErrorMessage(state, lookAhead int) string {
 
 	if yyDef[state] == -2 {
 		i := 0
-		for yyExca[i] != -1 || int(yyExca[i+1]) != state {
+		for yyExca[i] != -1 || yyExca[i+1] != state {
 			i += 2
 		}
 
 		// Look for tokens that we accept or reduce.
 		for i += 2; yyExca[i] >= 0; i += 2 {
-			tok := int(yyExca[i])
+			tok := yyExca[i]
 			if tok < TOKSTART || yyExca[i+1] == 0 {
 				continue
 			}
@@ -783,30 +772,30 @@ func yylex1(lex yyLexer, lval *yySymType) (char, token int) {
 	token = 0
 	char = lex.Lex(lval)
 	if char <= 0 {
-		token = int(yyTok1[0])
+		token = yyTok1[0]
 		goto out
 	}
 	if char < len(yyTok1) {
-		token = int(yyTok1[char])
+		token = yyTok1[char]
 		goto out
 	}
 	if char >= yyPrivate {
 		if char < yyPrivate+len(yyTok2) {
-			token = int(yyTok2[char-yyPrivate])
+			token = yyTok2[char-yyPrivate]
 			goto out
 		}
 	}
 	for i := 0; i < len(yyTok3); i += 2 {
-		token = int(yyTok3[i+0])
+		token = yyTok3[i+0]
 		if token == char {
-			token = int(yyTok3[i+1])
+			token = yyTok3[i+1]
 			goto out
 		}
 	}
 
 out:
 	if token == 0 {
-		token = int(yyTok2[1]) /* unknown char */
+		token = yyTok2[1] /* unknown char */
 	}
 	if yyDebug >= 3 {
 		__yyfmt__.Printf("lex %s(%d)\n", yyTokname(token), uint(char))
@@ -861,7 +850,7 @@ yystack:
 	yyS[yyp].yys = yystate
 
 yynewstate:
-	yyn = int(yyPact[yystate])
+	yyn = yyPact[yystate]
 	if yyn <= yyFlag {
 		goto yydefault /* simple state */
 	}
@@ -872,8 +861,8 @@ yynewstate:
 	if yyn < 0 || yyn >= yyLast {
 		goto yydefault
 	}
-	yyn = int(yyAct[yyn])
-	if int(yyChk[yyn]) == yytoken { /* valid shift */
+	yyn = yyAct[yyn]
+	if yyChk[yyn] == yytoken { /* valid shift */
 		yyrcvr.char = -1
 		yytoken = -1
 		yyVAL = yyrcvr.lval
@@ -886,7 +875,7 @@ yynewstate:
 
 yydefault:
 	/* default state action */
-	yyn = int(yyDef[yystate])
+	yyn = yyDef[yystate]
 	if yyn == -2 {
 		if yyrcvr.char < 0 {
 			yyrcvr.char, yytoken = yylex1(yylex, &yyrcvr.lval)
@@ -895,18 +884,18 @@ yydefault:
 		/* look through exception table */
 		xi := 0
 		for {
-			if yyExca[xi+0] == -1 && int(yyExca[xi+1]) == yystate {
+			if yyExca[xi+0] == -1 && yyExca[xi+1] == yystate {
 				break
 			}
 			xi += 2
 		}
 		for xi += 2; ; xi += 2 {
-			yyn = int(yyExca[xi+0])
+			yyn = yyExca[xi+0]
 			if yyn < 0 || yyn == yytoken {
 				break
 			}
 		}
-		yyn = int(yyExca[xi+1])
+		yyn = yyExca[xi+1]
 		if yyn < 0 {
 			goto ret0
 		}
@@ -928,10 +917,10 @@ yydefault:
 
 			/* find a state where "error" is a legal shift action */
 			for yyp >= 0 {
-				yyn = int(yyPact[yyS[yyp].yys]) + yyErrCode
+				yyn = yyPact[yyS[yyp].yys] + yyErrCode
 				if yyn >= 0 && yyn < yyLast {
-					yystate = int(yyAct[yyn]) /* simulate a shift of "error" */
-					if int(yyChk[yystate]) == yyErrCode {
+					yystate = yyAct[yyn] /* simulate a shift of "error" */
+					if yyChk[yystate] == yyErrCode {
 						goto yystack
 					}
 				}
@@ -967,7 +956,7 @@ yydefault:
 	yypt := yyp
 	_ = yypt // guard against "declared and not used"
 
-	yyp -= int(yyR2[yyn])
+	yyp -= yyR2[yyn]
 	// yyp is now the index of $0. Perform the default action. Iff the
 	// reduced production is ε, $1 is possibly out of range.
 	if yyp+1 >= len(yyS) {
@@ -978,16 +967,16 @@ yydefault:
 	yyVAL = yyS[yyp+1]
 
 	/* consult goto table to find next state */
-	yyn = int(yyR1[yyn])
-	yyg := int(yyPgo[yyn])
+	yyn = yyR1[yyn]
+	yyg := yyPgo[yyn]
 	yyj := yyg + yyS[yyp].yys + 1
 
 	if yyj >= yyLast {
-		yystate = int(yyAct[yyg])
+		yystate = yyAct[yyg]
 	} else {
-		yystate = int(yyAct[yyj])
-		if int(yyChk[yystate]) != -yyn {
-			yystate = int(yyAct[yyg])
+		yystate = yyAct[yyj]
+		if yyChk[yystate] != -yyn {
+			yystate = yyAct[yyg]
 		}
 	}
 	// dummy call; replaced with literal code
@@ -995,62 +984,52 @@ yydefault:
 
 	case 1:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:200
 		{
 			yylex.(*parser).generatedParserResult = yyDollar[2].labels
 		}
 	case 3:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:203
 		{
 			yylex.(*parser).addParseErrf(posrange.PositionRange{}, "no expression found in input")
 		}
 	case 4:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:205
 		{
 			yylex.(*parser).generatedParserResult = yyDollar[2].node
 		}
 	case 5:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:207
 		{
 			yylex.(*parser).generatedParserResult = yyDollar[2].node
 		}
 	case 7:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:210
 		{
 			yylex.(*parser).unexpected("", "")
 		}
 	case 20:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:233
 		{
 			yyVAL.node = yylex.(*parser).newAggregateExpr(yyDollar[1].item, yyDollar[2].node, yyDollar[3].node)
 		}
 	case 21:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:235
 		{
 			yyVAL.node = yylex.(*parser).newAggregateExpr(yyDollar[1].item, yyDollar[3].node, yyDollar[2].node)
 		}
 	case 22:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:237
 		{
 			yyVAL.node = yylex.(*parser).newAggregateExpr(yyDollar[1].item, &AggregateExpr{}, yyDollar[2].node)
 		}
 	case 23:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:239
 		{
 			yylex.(*parser).unexpected("aggregation", "")
 			yyVAL.node = yylex.(*parser).newAggregateExpr(yyDollar[1].item, &AggregateExpr{}, Expressions{})
 		}
 	case 24:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:247
 		{
 			yyVAL.node = &AggregateExpr{
 				Grouping: yyDollar[2].strings,
@@ -1058,7 +1037,6 @@ yydefault:
 		}
 	case 25:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:253
 		{
 			yyVAL.node = &AggregateExpr{
 				Grouping: yyDollar[2].strings,
@@ -1067,103 +1045,86 @@ yydefault:
 		}
 	case 26:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:266
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 27:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:267
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 28:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:268
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 29:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:269
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 30:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:270
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 31:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:271
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 32:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:272
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 33:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:273
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 34:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:274
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 35:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:275
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 36:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:276
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 37:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:277
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 38:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:278
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 39:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:279
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 40:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:280
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 41:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:281
 		{
 			yyVAL.node = yylex.(*parser).newBinaryExpression(yyDollar[1].node, yyDollar[2].item, yyDollar[3].node, yyDollar[4].node)
 		}
 	case 43:
 		yyDollar = yyS[yypt-0 : yypt+1]
-//line promql/parser/generated_parser.y:289
 		{
 			yyVAL.node = &BinaryExpr{
 				VectorMatching: &VectorMatching{Card: CardOneToOne},
@@ -1171,7 +1132,6 @@ yydefault:
 		}
 	case 44:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:294
 		{
 			yyVAL.node = &BinaryExpr{
 				VectorMatching: &VectorMatching{Card: CardOneToOne},
@@ -1180,14 +1140,12 @@ yydefault:
 		}
 	case 45:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:302
 		{
 			yyVAL.node = yyDollar[1].node
 			yyVAL.node.(*BinaryExpr).VectorMatching.MatchingLabels = yyDollar[3].strings
 		}
 	case 46:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:307
 		{
 			yyVAL.node = yyDollar[1].node
 			yyVAL.node.(*BinaryExpr).VectorMatching.MatchingLabels = yyDollar[3].strings
@@ -1195,7 +1153,6 @@ yydefault:
 		}
 	case 49:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:317
 		{
 			yyVAL.node = yyDollar[1].node
 			yyVAL.node.(*BinaryExpr).VectorMatching.Card = CardManyToOne
@@ -1203,7 +1160,6 @@ yydefault:
 		}
 	case 50:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:323
 		{
 			yyVAL.node = yyDollar[1].node
 			yyVAL.node.(*BinaryExpr).VectorMatching.Card = CardOneToMany
@@ -1211,51 +1167,43 @@ yydefault:
 		}
 	case 51:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:332
 		{
 			yyVAL.strings = yyDollar[2].strings
 		}
 	case 52:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:334
 		{
 			yyVAL.strings = yyDollar[2].strings
 		}
 	case 53:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:336
 		{
 			yyVAL.strings = []string{}
 		}
 	case 54:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:338
 		{
 			yylex.(*parser).unexpected("grouping opts", "\"(\"")
 			yyVAL.strings = nil
 		}
 	case 55:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:344
 		{
 			yyVAL.strings = append(yyDollar[1].strings, yyDollar[3].item.Val)
 		}
 	case 56:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:346
 		{
 			yyVAL.strings = []string{yyDollar[1].item.Val}
 		}
 	case 57:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:348
 		{
 			yylex.(*parser).unexpected("grouping opts", "\",\" or \")\"")
 			yyVAL.strings = yyDollar[1].strings
 		}
 	case 58:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:352
 		{
 			if !isLabel(yyDollar[1].item.Val) {
 				yylex.(*parser).unexpected("grouping opts", "label")
@@ -1264,14 +1212,12 @@ yydefault:
 		}
 	case 59:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:359
 		{
 			yylex.(*parser).unexpected("grouping opts", "label")
 			yyVAL.item = Item{}
 		}
 	case 60:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:367
 		{
 			fn, exist := getFunction(yyDollar[1].item.Val, yylex.(*parser).functions)
 			if !exist {
@@ -1291,86 +1237,73 @@ yydefault:
 		}
 	case 61:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:387
 		{
 			yyVAL.node = yyDollar[2].node
 		}
 	case 62:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:389
 		{
 			yyVAL.node = Expressions{}
 		}
 	case 63:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:393
 		{
 			yyVAL.node = append(yyDollar[1].node.(Expressions), yyDollar[3].node.(Expr))
 		}
 	case 64:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:395
 		{
 			yyVAL.node = Expressions{yyDollar[1].node.(Expr)}
 		}
 	case 65:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:397
 		{
 			yylex.(*parser).addParseErrf(yyDollar[2].item.PositionRange(), "trailing commas not allowed in function call args")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 66:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:408
 		{
 			yyVAL.node = &ParenExpr{Expr: yyDollar[2].node.(Expr), PosRange: mergeRanges(&yyDollar[1].item, &yyDollar[3].item)}
 		}
 	case 67:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:416
 		{
 			yylex.(*parser).addOffset(yyDollar[1].node, yyDollar[3].duration)
 			yyVAL.node = yyDollar[1].node
 		}
 	case 68:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:421
 		{
 			yylex.(*parser).addOffset(yyDollar[1].node, -yyDollar[4].duration)
 			yyVAL.node = yyDollar[1].node
 		}
 	case 69:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:426
 		{
 			yylex.(*parser).unexpected("offset", "duration")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 70:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:433
 		{
 			yylex.(*parser).setTimestamp(yyDollar[1].node, yyDollar[3].float)
 			yyVAL.node = yyDollar[1].node
 		}
 	case 71:
 		yyDollar = yyS[yypt-5 : yypt+1]
-//line promql/parser/generated_parser.y:438
 		{
 			yylex.(*parser).setAtModifierPreprocessor(yyDollar[1].node, yyDollar[3].item)
 			yyVAL.node = yyDollar[1].node
 		}
 	case 72:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:443
 		{
 			yylex.(*parser).unexpected("@", "timestamp")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 75:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:453
 		{
 			var errMsg string
 			vs, ok := yyDollar[1].node.(*VectorSelector)
@@ -1395,7 +1328,6 @@ yydefault:
 		}
 	case 76:
 		yyDollar = yyS[yypt-6 : yypt+1]
-//line promql/parser/generated_parser.y:478
 		{
 			yyVAL.node = &SubqueryExpr{
 				Expr:  yyDollar[1].node.(Expr),
@@ -1407,35 +1339,30 @@ yydefault:
 		}
 	case 77:
 		yyDollar = yyS[yypt-6 : yypt+1]
-//line promql/parser/generated_parser.y:488
 		{
 			yylex.(*parser).unexpected("subquery selector", "\"]\"")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 78:
 		yyDollar = yyS[yypt-5 : yypt+1]
-//line promql/parser/generated_parser.y:490
 		{
 			yylex.(*parser).unexpected("subquery selector", "duration or \"]\"")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 79:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:492
 		{
 			yylex.(*parser).unexpected("subquery or range", "\":\" or \"]\"")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 80:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:494
 		{
 			yylex.(*parser).unexpected("subquery selector", "duration")
 			yyVAL.node = yyDollar[1].node
 		}
 	case 81:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:504
 		{
 			if nl, ok := yyDollar[2].node.(*NumberLiteral); ok {
 				if yyDollar[1].item.Typ == SUB {
@@ -1449,7 +1376,6 @@ yydefault:
 		}
 	case 82:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:522
 		{
 			vs := yyDollar[2].node.(*VectorSelector)
 			vs.PosRange = mergeRanges(&yyDollar[1].item, vs)
@@ -1459,7 +1385,6 @@ yydefault:
 		}
 	case 83:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:530
 		{
 			vs := &VectorSelector{
 				Name:          yyDollar[1].item.Val,
@@ -1471,7 +1396,6 @@ yydefault:
 		}
 	case 84:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:540
 		{
 			vs := yyDollar[1].node.(*VectorSelector)
 			yylex.(*parser).assembleVectorSelector(vs)
@@ -1479,7 +1403,6 @@ yydefault:
 		}
 	case 85:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:548
 		{
 			yyVAL.node = &VectorSelector{
 				LabelMatchers: yyDollar[2].matchers,
@@ -1488,7 +1411,6 @@ yydefault:
 		}
 	case 86:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:555
 		{
 			yyVAL.node = &VectorSelector{
 				LabelMatchers: yyDollar[2].matchers,
@@ -1497,7 +1419,6 @@ yydefault:
 		}
 	case 87:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:562
 		{
 			yyVAL.node = &VectorSelector{
 				LabelMatchers: []*labels.Matcher{},
@@ -1506,7 +1427,6 @@ yydefault:
 		}
 	case 88:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:571
 		{
 			if yyDollar[1].matchers != nil {
 				yyVAL.matchers = append(yyDollar[1].matchers, yyDollar[3].matcher)
@@ -1516,186 +1436,168 @@ yydefault:
 		}
 	case 89:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:579
 		{
 			yyVAL.matchers = []*labels.Matcher{yyDollar[1].matcher}
 		}
 	case 90:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:581
 		{
 			yylex.(*parser).unexpected("label matching", "\",\" or \"}\"")
 			yyVAL.matchers = yyDollar[1].matchers
 		}
 	case 91:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:585
 		{
 			yyVAL.matcher = yylex.(*parser).newLabelMatcher(yyDollar[1].item, yyDollar[2].item, yyDollar[3].item)
 		}
 	case 92:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:587
+		{
+			yyVAL.matcher = yylex.(*parser).newLabelMatcher(yyDollar[1].item, yyDollar[2].item, yyDollar[3].item)
+		}
+	case 93:
+		yyDollar = yyS[yypt-1 : yypt+1]
+		{
+			yyVAL.matcher = yylex.(*parser).newMetricNameMatcher(yyDollar[1].item)
+		}
+	case 94:
+		yyDollar = yyS[yypt-3 : yypt+1]
 		{
 			yylex.(*parser).unexpected("label matching", "string")
 			yyVAL.matcher = nil
 		}
-	case 93:
+	case 95:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:589
 		{
 			yylex.(*parser).unexpected("label matching", "label matching operator")
 			yyVAL.matcher = nil
 		}
-	case 94:
+	case 96:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:591
 		{
 			yylex.(*parser).unexpected("label matching", "identifier or \"}\"")
 			yyVAL.matcher = nil
 		}
-	case 95:
+	case 97:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:599
 		{
 			b := labels.NewBuilder(yyDollar[2].labels)
 			b.Set(labels.MetricName, yyDollar[1].item.Val)
 			yyVAL.labels = b.Labels()
 		}
-	case 96:
+	case 98:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:601
 		{
 			yyVAL.labels = yyDollar[1].labels
 		}
-	case 119:
-		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:608
-		{
-			yyVAL.labels = labels.New(yyDollar[2].lblList...)
-		}
-	case 120:
-		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:610
-		{
-			yyVAL.labels = labels.New(yyDollar[2].lblList...)
-		}
 	case 121:
-		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:612
+		yyDollar = yyS[yypt-3 : yypt+1]
 		{
-			yyVAL.labels = labels.New()
+			yyVAL.labels = labels.New(yyDollar[2].lblList...)
 		}
 	case 122:
-		yyDollar = yyS[yypt-0 : yypt+1]
-//line promql/parser/generated_parser.y:614
+		yyDollar = yyS[yypt-4 : yypt+1]
+		{
+			yyVAL.labels = labels.New(yyDollar[2].lblList...)
+		}
+	case 123:
+		yyDollar = yyS[yypt-2 : yypt+1]
 		{
 			yyVAL.labels = labels.New()
 		}
-	case 123:
+	case 124:
+		yyDollar = yyS[yypt-0 : yypt+1]
+		{
+			yyVAL.labels = labels.New()
+		}
+	case 125:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:618
 		{
 			yyVAL.lblList = append(yyDollar[1].lblList, yyDollar[3].label)
 		}
-	case 124:
+	case 126:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:620
 		{
 			yyVAL.lblList = []labels.Label{yyDollar[1].label}
 		}
-	case 125:
+	case 127:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:622
 		{
 			yylex.(*parser).unexpected("label set", "\",\" or \"}\"")
 			yyVAL.lblList = yyDollar[1].lblList
 		}
-	case 126:
+	case 128:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:627
 		{
 			yyVAL.label = labels.Label{Name: yyDollar[1].item.Val, Value: yylex.(*parser).unquoteString(yyDollar[3].item.Val)}
 		}
-	case 127:
+	case 129:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:629
 		{
 			yylex.(*parser).unexpected("label set", "string")
 			yyVAL.label = labels.Label{}
 		}
-	case 128:
+	case 130:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:631
 		{
 			yylex.(*parser).unexpected("label set", "\"=\"")
 			yyVAL.label = labels.Label{}
 		}
-	case 129:
+	case 131:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:633
 		{
 			yylex.(*parser).unexpected("label set", "identifier or \"}\"")
 			yyVAL.label = labels.Label{}
 		}
-	case 130:
+	case 132:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:644
 		{
 			yylex.(*parser).generatedParserResult = &seriesDescription{
 				labels: yyDollar[1].labels,
 				values: yyDollar[2].series,
 			}
 		}
-	case 131:
+	case 133:
 		yyDollar = yyS[yypt-0 : yypt+1]
-//line promql/parser/generated_parser.y:653
 		{
 			yyVAL.series = []SequenceValue{}
 		}
-	case 132:
+	case 134:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:655
 		{
 			yyVAL.series = append(yyDollar[1].series, yyDollar[3].series...)
 		}
-	case 133:
+	case 135:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:657
 		{
 			yyVAL.series = yyDollar[1].series
 		}
-	case 134:
+	case 136:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:659
 		{
 			yylex.(*parser).unexpected("series values", "")
 			yyVAL.series = nil
 		}
-	case 135:
+	case 137:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:663
 		{
 			yyVAL.series = []SequenceValue{{Omitted: true}}
 		}
-	case 136:
+	case 138:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:665
 		{
 			yyVAL.series = []SequenceValue{}
 			for i := uint64(0); i < yyDollar[3].uint; i++ {
 				yyVAL.series = append(yyVAL.series, SequenceValue{Omitted: true})
 			}
 		}
-	case 137:
+	case 139:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:672
 		{
 			yyVAL.series = []SequenceValue{{Value: yyDollar[1].float}}
 		}
-	case 138:
+	case 140:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:674
 		{
 			yyVAL.series = []SequenceValue{}
 			// Add an additional value for time 0, which we ignore in tests.
@@ -1703,9 +1605,8 @@ yydefault:
 				yyVAL.series = append(yyVAL.series, SequenceValue{Value: yyDollar[1].float})
 			}
 		}
-	case 139:
+	case 141:
 		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:682
 		{
 			yyVAL.series = []SequenceValue{}
 			// Add an additional value for time 0, which we ignore in tests.
@@ -1714,15 +1615,13 @@ yydefault:
 				yyDollar[1].float += yyDollar[2].float
 			}
 		}
-	case 140:
+	case 142:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:692
 		{
 			yyVAL.series = []SequenceValue{{Histogram: yyDollar[1].histogram}}
 		}
-	case 141:
+	case 143:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:696
 		{
 			yyVAL.series = []SequenceValue{}
 			// Add an additional value for time 0, which we ignore in tests.
@@ -1731,9 +1630,8 @@ yydefault:
 				//$1 += $2
 			}
 		}
-	case 142:
+	case 144:
 		yyDollar = yyS[yypt-5 : yypt+1]
-//line promql/parser/generated_parser.y:705
 		{
 			val, err := yylex.(*parser).histogramsIncreaseSeries(yyDollar[1].histogram, yyDollar[3].histogram, yyDollar[5].uint)
 			if err != nil {
@@ -1741,9 +1639,8 @@ yydefault:
 			}
 			yyVAL.series = val
 		}
-	case 143:
+	case 145:
 		yyDollar = yyS[yypt-5 : yypt+1]
-//line promql/parser/generated_parser.y:713
 		{
 			val, err := yylex.(*parser).histogramsDecreaseSeries(yyDollar[1].histogram, yyDollar[3].histogram, yyDollar[5].uint)
 			if err != nil {
@@ -1751,176 +1648,150 @@ yydefault:
 			}
 			yyVAL.series = val
 		}
-	case 144:
+	case 146:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:723
 		{
 			if yyDollar[1].item.Val != "stale" {
 				yylex.(*parser).unexpected("series values", "number or \"stale\"")
 			}
 			yyVAL.float = math.Float64frombits(value.StaleNaN)
 		}
-	case 147:
-		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:735
-		{
-			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&yyDollar[2].descriptors)
-		}
-	case 148:
-		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:739
-		{
-			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&yyDollar[2].descriptors)
-		}
 	case 149:
-		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:743
+		yyDollar = yyS[yypt-4 : yypt+1]
 		{
-			m := yylex.(*parser).newMap()
-			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&m)
+			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&yyDollar[2].descriptors)
 		}
 	case 150:
-		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:748
+		yyDollar = yyS[yypt-3 : yypt+1]
 		{
-			m := yylex.(*parser).newMap()
-			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&m)
+			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&yyDollar[2].descriptors)
 		}
 	case 151:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:756
+		{
+			m := yylex.(*parser).newMap()
+			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&m)
+		}
+	case 152:
+		yyDollar = yyS[yypt-2 : yypt+1]
+		{
+			m := yylex.(*parser).newMap()
+			yyVAL.histogram = yylex.(*parser).buildHistogramFromMap(&m)
+		}
+	case 153:
+		yyDollar = yyS[yypt-3 : yypt+1]
 		{
 			yyVAL.descriptors = *(yylex.(*parser).mergeMaps(&yyDollar[1].descriptors, &yyDollar[3].descriptors))
 		}
-	case 152:
+	case 154:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:760
 		{
 			yyVAL.descriptors = yyDollar[1].descriptors
 		}
-	case 153:
+	case 155:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:763
 		{
 			yylex.(*parser).unexpected("histogram description", "histogram description key, e.g. buckets:[5 10 7]")
 		}
-	case 154:
+	case 156:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:770
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["schema"] = yyDollar[3].int
 		}
-	case 155:
+	case 157:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:775
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["sum"] = yyDollar[3].float
 		}
-	case 156:
+	case 158:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:780
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["count"] = yyDollar[3].float
 		}
-	case 157:
+	case 159:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:785
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["z_bucket"] = yyDollar[3].float
 		}
-	case 158:
+	case 160:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:790
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["z_bucket_w"] = yyDollar[3].float
 		}
-	case 159:
+	case 161:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:795
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["buckets"] = yyDollar[3].bucket_set
 		}
-	case 160:
+	case 162:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:800
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["offset"] = yyDollar[3].int
 		}
-	case 161:
+	case 163:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:805
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["n_buckets"] = yyDollar[3].bucket_set
 		}
-	case 162:
+	case 164:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:810
 		{
 			yyVAL.descriptors = yylex.(*parser).newMap()
 			yyVAL.descriptors["n_offset"] = yyDollar[3].int
 		}
-	case 163:
-		yyDollar = yyS[yypt-4 : yypt+1]
-//line promql/parser/generated_parser.y:817
-		{
-			yyVAL.bucket_set = yyDollar[2].bucket_set
-		}
-	case 164:
-		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:821
-		{
-			yyVAL.bucket_set = yyDollar[2].bucket_set
-		}
 	case 165:
+		yyDollar = yyS[yypt-4 : yypt+1]
+		{
+			yyVAL.bucket_set = yyDollar[2].bucket_set
+		}
+	case 166:
+		yyDollar = yyS[yypt-3 : yypt+1]
+		{
+			yyVAL.bucket_set = yyDollar[2].bucket_set
+		}
+	case 167:
 		yyDollar = yyS[yypt-3 : yypt+1]
-//line promql/parser/generated_parser.y:827
 		{
 			yyVAL.bucket_set = append(yyDollar[1].bucket_set, yyDollar[3].float)
 		}
-	case 166:
+	case 168:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:831
 		{
 			yyVAL.bucket_set = []float64{yyDollar[1].float}
 		}
-	case 213:
+	case 215:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:856
 		{
 			yyVAL.node = &NumberLiteral{
 				Val:      yylex.(*parser).number(yyDollar[1].item.Val),
 				PosRange: yyDollar[1].item.PositionRange(),
 			}
 		}
-	case 214:
+	case 216:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:864
 		{
 			yyVAL.float = yylex.(*parser).number(yyDollar[1].item.Val)
 		}
-	case 215:
+	case 217:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:866
 		{
 			yyVAL.float = yyDollar[2].float
 		}
-	case 216:
+	case 218:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:867
 		{
 			yyVAL.float = -yyDollar[2].float
 		}
-	case 219:
+	case 221:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:873
 		{
 			var err error
 			yyVAL.uint, err = strconv.ParseUint(yyDollar[1].item.Val, 10, 64)
@@ -1928,21 +1799,18 @@ yydefault:
 				yylex.(*parser).addParseErrf(yyDollar[1].item.PositionRange(), "invalid repetition in series values: %s", err)
 			}
 		}
-	case 220:
+	case 222:
 		yyDollar = yyS[yypt-2 : yypt+1]
-//line promql/parser/generated_parser.y:882
 		{
 			yyVAL.int = -int64(yyDollar[2].uint)
 		}
-	case 221:
+	case 223:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:883
 		{
 			yyVAL.int = int64(yyDollar[1].uint)
 		}
-	case 222:
+	case 224:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:887
 		{
 			var err error
 			yyVAL.duration, err = parseDuration(yyDollar[1].item.Val)
@@ -1950,24 +1818,30 @@ yydefault:
 				yylex.(*parser).addParseErr(yyDollar[1].item.PositionRange(), err)
 			}
 		}
-	case 223:
+	case 225:
 		yyDollar = yyS[yypt-1 : yypt+1]
-//line promql/parser/generated_parser.y:898
 		{
 			yyVAL.node = &StringLiteral{
 				Val:      yylex.(*parser).unquoteString(yyDollar[1].item.Val),
 				PosRange: yyDollar[1].item.PositionRange(),
 			}
 		}
-	case 224:
+	case 226:
+		yyDollar = yyS[yypt-1 : yypt+1]
+		{
+			yyVAL.item = Item{
+				Typ: METRIC_IDENTIFIER,
+				Pos: yyDollar[1].item.PositionRange().Start,
+				Val: yylex.(*parser).unquoteString(yyDollar[1].item.Val),
+			}
+		}
+	case 227:
 		yyDollar = yyS[yypt-0 : yypt+1]
-//line promql/parser/generated_parser.y:911
 		{
 			yyVAL.duration = 0
 		}
-	case 226:
+	case 229:
 		yyDollar = yyS[yypt-0 : yypt+1]
-//line promql/parser/generated_parser.y:915
 		{
 			yyVAL.strings = nil
 		}
diff --git a/promql/parser/parse.go b/promql/parser/parse.go
index d266a1f21..6a05e4a79 100644
--- a/promql/parser/parse.go
+++ b/promql/parser/parse.go
@@ -791,6 +791,18 @@ func (p *parser) checkAST(node Node) (typ ValueType) {
 			// Skip the check for non-empty matchers because an explicit
 			// metric name is a non-empty matcher.
 			break
+		} else {
+			// We also have to make sure a metric name was not set twice inside the
+			// braces.
+			foundMetricName := ""
+			for _, m := range n.LabelMatchers {
+				if m != nil && m.Name == labels.MetricName {
+					if foundMetricName != "" {
+						p.addParseErrf(n.PositionRange(), "metric name must not be set twice: %q or %q", foundMetricName, m.Value)
+					}
+					foundMetricName = m.Value
+				}
+			}
 		}
 
 		// A Vector selector must contain at least one non-empty matcher to prevent
@@ -874,6 +886,15 @@ func (p *parser) newLabelMatcher(label, operator, value Item) *labels.Matcher {
 	return m
 }
 
+func (p *parser) newMetricNameMatcher(value Item) *labels.Matcher {
+	m, err := labels.NewMatcher(labels.MatchEqual, labels.MetricName, value.Val)
+	if err != nil {
+		p.addParseErr(value.PositionRange(), err)
+	}
+
+	return m
+}
+
 // addOffset is used to set the offset in the generated parser.
 func (p *parser) addOffset(e Node, offset time.Duration) {
 	var orgoffsetp *time.Duration