Namespace: go.std.go.build.constraint

v1.0

Contents

• Summary
• Index
• Constants
• Variables
• Functions, Macros, and Special Forms
• Types

Summary

Provides a low-level interface to the go/build/constraint package.

Package constraint implements parsing and evaluation of build constraint lines.
See https://golang.org/cmd/go/#hdr-Build_constraints for documentation about build constraints themselves.

This package parses both the original “// +build” syntax and the “//go:build” syntax that will be added in Go 1.17.
The parser is being included in Go 1.16 to allow tools that need to process Go 1.17 source code
to still be built against the Go 1.16 release.
See https://golang.org/design/draft-gobuild for details about the “//go:build” syntax.

Index

• *AndExpr
• *NotExpr
• *OrExpr
• *SyntaxError
• *TagExpr
• AndExpr
• Expr
• IsGoBuild
• IsPlusBuild
• NotExpr
• OrExpr
• Parse
• PlusBuildLines
• SyntaxError
• TagExpr
• arrayOfAndExpr
• arrayOfExpr
• arrayOfNotExpr
• arrayOfOrExpr
• arrayOfSyntaxError
• arrayOfTagExpr

Legend

Constant Variable Function Macro Special form Type GoVar Receiver/Method

Constants

Constants are variables with :const true in their metadata. Joker currently does not recognize them as special; as such, it allows redefining them or their values.

(None.)

Variables

(None.)

Functions, Macros, and Special Forms

• IsGoBuild

  Function v1.0

  (IsGoBuild line)
  

  IsGoBuild reports whether the line of text is a “//go:build” constraint.
  It only checks the prefix of the text, not that the expression itself parses.
  
  Go input arguments: (line string)
  
  Go returns: bool
  
  Joker input arguments: [^String line]
  
  Joker returns: ^Boolean

• IsPlusBuild

  Function v1.0

  (IsPlusBuild line)
  

  IsPlusBuild reports whether the line of text is a “// +build” constraint.
  It only checks the prefix of the text, not that the expression itself parses.
  
  Go input arguments: (line string)
  
  Go returns: bool
  
  Joker input arguments: [^String line]
  
  Joker returns: ^Boolean

• Parse

  Function v1.0

  (Parse line)
  

  Parse parses a single build constraint line of the form “//go:build ...” or “// +build ...”
  and returns the corresponding boolean expression.
  
  Go input arguments: (line string)
  
  Go returns: (Expr, error)
  
  Joker input arguments: [^String line]
  
  Joker returns: [^Expr, ^Error]

• PlusBuildLines

  Function v1.0

  (PlusBuildLines x)
  

  PlusBuildLines returns a sequence of “// +build” lines that evaluate to the build expression x.
  If the expression is too complex to convert directly to “// +build” lines, PlusBuildLines returns an error.
  
  Go input arguments: (x Expr)
  
  Go returns: ([]string, error)
  
  Joker input arguments: [^Expr x]
  
  Joker returns: [^arrayOfString, ^Error]

Types

• *AndExpr

  Concrete Type v1.0

  An AndExpr represents the expression X && Y.
  

• String

  Receiver for *AndExpr v1.0

  ([])
  

• *NotExpr

  Concrete Type v1.0

  A NotExpr represents the expression !X (the negation of X).
  

• String

  Receiver for *NotExpr v1.0

  ([])
  

• *OrExpr

  Concrete Type v1.0

  An OrExpr represents the expression X || Y.
  

• String

  Receiver for *OrExpr v1.0

  ([])
  

• *SyntaxError

  Concrete Type v1.0

  A SyntaxError reports a syntax error in a parsed build expression.
  

• Error

  Receiver for *SyntaxError v1.0

  ([])
  

• *TagExpr

  Concrete Type v1.0

  A TagExpr is an Expr for the single tag Tag.
  

• String

  Receiver for *TagExpr v1.0

  ([])
  

• AndExpr

  Concrete Type v1.0

  An AndExpr represents the expression X && Y.
  

• Expr

  Abstract Type v1.0

  An Expr is a build tag constraint expression.
  The underlying concrete type is *AndExpr, *OrExpr, *NotExpr, or *TagExpr.
  

• String

  Method for Expr v1.0

  ([])
  

• NotExpr

  Concrete Type v1.0

  A NotExpr represents the expression !X (the negation of X).
  

• OrExpr

  Concrete Type v1.0

  An OrExpr represents the expression X || Y.
  

• SyntaxError

  Concrete Type v1.0

  A SyntaxError reports a syntax error in a parsed build expression.
  

• TagExpr

  Concrete Type v1.0

  A TagExpr is an Expr for the single tag Tag.
  

• arrayOfAndExpr

  Concrete Type v1.0

  An AndExpr represents the expression X && Y.
  

• arrayOfExpr

  Concrete Type v1.0

  An Expr is a build tag constraint expression.
  The underlying concrete type is *AndExpr, *OrExpr, *NotExpr, or *TagExpr.
  

• arrayOfNotExpr

  Concrete Type v1.0

  A NotExpr represents the expression !X (the negation of X).
  

• arrayOfOrExpr

  Concrete Type v1.0

  An OrExpr represents the expression X || Y.
  

• arrayOfSyntaxError

  Concrete Type v1.0

  A SyntaxError reports a syntax error in a parsed build expression.
  

• arrayOfTagExpr

  Concrete Type v1.0

  A TagExpr is an Expr for the single tag Tag.