case ')':
				tok = in.Stack.Next() // First token of macro definition.
				break Loop
			case ',':
				if acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				acceptArg = true
			case scanner.Ident:
				if !acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				arg := in.Stack.Text()
				if i := lookup(args, arg); i >= 0 {

					goto next
				}
			}
			if tok == scanner.EOF {
				p.errorf("unexpected EOF")
				return "", "", nil, false
			}
			// Split operands on comma. Also, the old syntax on x86 for a "register pair"
			// was AX:DX, for which the new syntax is DX, AX. Note the reordering.
			if tok == '\n' || tok == ';' || (nesting == 0 && (tok == ',' || tok == ':')) {
				if tok == ':' {

	JCS	2(PC)
	JMP	(AX)(AX*4)
	JCS	2(PC)
	JMP	R13

// LTYPEN spec4	{ outcode($1, &$2); }
	NOP
	NOP	AX
	NOP	foo+4(SB)

// LTYPES spec5	{ outcode($1, &$2); }
	SHLL	CX, R12
	SHLL	CX, foo+4(SB)
	// Old syntax, still accepted:
	SHLL	CX, R11:AX // SHLL CX, AX, R11

// LTYPEM spec6	{ outcode($1, &$2); }
	MOVL	AX, R11
	MOVL	$4, R11
//	MOVL	AX, 0(AX):DS // no longer works - did it ever?

+ If there is a corresponding issue, add either `Fixes #1234` or `Updates #1234`
  (the latter if this is not a complete fix) to this comment
+ If referring to a repo other than `golang/go` you can use the
  `owner/repo#issue_number` syntax: `Fixes golang/tools#1234`
+ We do not use Signed-off-by lines in Go. Please don't add them.
  Our Gerrit server & GitHub bots enforce CLA compliance instead.

dependencies.
</p>

<p>
The syntax is compact and simple to parse, allowing for easy analysis
by automatic tools such as integrated development environments.
</p>

<h2 id="Notation">Notation</h2>
<p>
The syntax is specified using a
<a href="https://en.wikipedia.org/wiki/Wirth_syntax_notation">variant</a>
of Extended Backus-Naur Form (EBNF):
</p>

<pre class="grammar">
Syntax      = { Production } .

				override[id.Name] = new
			}
		}
	}

	// Apply overrides.
	for old, new := range override {
		if id := goIdent[old]; id != nil {
			id.Name = new
		}
	}

	// Any names still using the _C syntax are not going to compile,
	// although in general we don't know whether they all made it
	// into the file, so we can't warn here.
	//
	// The most common case is union types, which begin with

pkg regexp/syntax, const InstRuneAny = 9
pkg regexp/syntax, const InstRuneAnyNotNL = 10
pkg regexp/syntax, const Literal = 2
pkg regexp/syntax, const MatchNL = 12
pkg regexp/syntax, const NonGreedy = 32
pkg regexp/syntax, const OneLine = 16
pkg regexp/syntax, const OpAlternate = 19
pkg regexp/syntax, const OpAnyChar = 6
pkg regexp/syntax, const OpAnyCharNotNL = 5
pkg regexp/syntax, const OpBeginLine = 7

<a href="https://9p.io/sys/doc/asm.html">elsewhere</a>.
If you plan to write assembly language, you should read that document although much of it is Plan 9-specific.
The current document provides a summary of the syntax and the differences with
what is explained in that document, and
describes the peculiarities that apply when writing assembly code to interact with Go.
</p>

<p>

together. The directive can include a list of build constraints limiting its
effect to systems satisfying one of the constraints
(see https://golang.org/pkg/go/build/#hdr-Build_Constraints for details about the constraint syntax).
For example:

	// #cgo CFLAGS: -DPNG_DEBUG=1
	// #cgo amd64 386 CFLAGS: -DX86=1
	// #cgo LDFLAGS: -lpng
	// #include <png.h>
	import "C"

name can appear multiple times the returned Values can contain
more than one value for a given key.

The new [ParseSetCookie] function parses a Set-Cookie header value and