▼Syntax Color:   Utilities
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racket-lexer
racket-lexer*
racket-lexer/  status
racket-lexer*/  status
racket-nobar-lexer/  status
racket-nobar-lexer*/  status
current-lexeme->semantic-type-guess
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3 Racket Lexer🔗ℹ

 (require syntax-color/racket-lexer)
  package: syntax-color-lib

procedure

(racket-lexer in) → 
(or/c string? eof-object?)
symbol?
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
  in : input-port?
A lexer for Racket, including reader extensions (Reader Extension), built specifically for color:text<%>.

The racket-lexer function returns 5 values:

  • Either a string containing the matching text or the eof object. Block comments and specials currently return an empty string. This may change in the future to other string or non-string data.

  • A symbol in '(error comment sexp-comment white-space constant string no-color parenthesis hash-colon-keyword symbol eof other).

  • A symbol in '(|(| |)| |[| |]| |{| |}|) or #f.

  • A number representing the starting position of the match (or #f if eof).

  • A number representing the ending position of the match (or #f if eof).

procedure

(racket-lexer* in offset mode)

 → 
(or/c string? eof-object?)
(or/c symbol?
      (and/c (hash/c symbol? any/c) immutable?))
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
exact-nonnegative-integer?
any/c
  in : input-port?
  offset : exact-nonnegative-integer?
  mode : any/c
Like racket-lexer, but uses the extended lexer protocol to track and report regions that are commented out with #;. It also uses current-lexeme->semantic-type-guess to potentially add 'semantic-type-guess to the second result.

Added in version 1.2 of package syntax-color-lib.
Changed in version 1.7: Added use of current-lexeme->semantic-type-guess.

procedure

(racket-lexer/status in) → 
(or/c string? eof-object?)
symbol?
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
(or/c 'datum 'open 'close 'continue)
  in : input-port?
Like racket-lexer, but returns an extra value. The last return value indicates whether the consumed token should count as a datum, an opening parenthesis (or similar starting token to group other tokens), a closing parenthesis (or similar), or a prefix (such as whitespace) on a datum.

procedure

(racket-lexer*/status in offset mode)

 → 
(or/c string? eof-object?)
(or/c symbol?
      (and/c (hash/c symbol? any/c) immutable?))
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
exact-nonnegative-integer?
any/c
(or/c 'datum 'open 'close 'continue)
  in : input-port?
  offset : exact-nonnegative-integer?
  mode : any/c
Like racket-lexer/status, but with comment tracking and 'semantic-type-guess addition like racket-lexer*.

Added in version 1.2 of package syntax-color-lib.
Changed in version 1.7: Added use of current-lexeme->semantic-type-guess.

procedure

(racket-nobar-lexer/status in)

 → 
(or/c string? eof-object?)
symbol?
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
(or/c 'datum 'open 'close 'continue)
  in : input-port?
Like racket-lexer/status, except it treats | as a delimiter instead of quoting syntax for a symbol. This function is used by scribble-lexer.

procedure

(racket-nobar-lexer*/status in offset mode)

 → 
(or/c string? eof-object?)
(or/c symbol?
      (and/c (hash/c symbol? any/c) immutable?))
(or/c symbol? #f)
(or/c number? #f)
(or/c number? #f)
exact-nonnegative-integer?
any/c
(or/c 'datum 'open 'close 'continue)
  in : input-port?
  offset : exact-nonnegative-integer?
  mode : any/c
Like racket-nobar-lexer/status, but with comment tracking and 'semantic-type-guess addition like racket-lexer*.

Added in version 1.2 of package syntax-color-lib.
Changed in version 1.7: Added use of current-lexeme->semantic-type-guess.

parameter

(current-lexeme->semantic-type-guess)

 → (string . -> . (or/c #f symbol?))
(current-lexeme->semantic-type-guess proc) → void?
  proc : (string . -> . (or/c #f symbol?))
A parameter to determine when a 'semantic-type-guess attribute should be added to a token result of type 'symbol by racket-lexer* and similar functions. An attribute is added whenever the proc value of the parameter returns a symbol (instead of #f).

Added in version 1.7 of package syntax-color-lib.

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