Create a PoC for syntax extension that injects line number

[jcubic]

It would be cool if that would be possible. It will only work when the source code is the text file and not the binary.

The Lexer would need to be modified to count new lines.

Think about the possibility of adding a function that will return line number.

• Working Example
• Update documentation

[jcubic]

The Lexer already have metadata information like number of columns or line number. There is only a need to expose this to the user. This will also allow adding line number to stack trace.

[jcubic]

This a working example:

(set-special! "#:num" 'line-num lips.specials.SYMBOL)

(define (line-num)
  (let ((token (lips.__parser__.__lexer__.peek true)))
    (+ token.line 1)))

(print #:num) ;; ==> 7
(print #:num) ;; ==> 8

[jcubic]

With this, there will be a way to add full string interpolation #321

This is example dumb raw string syntax:

(set-special! "#raw" 'frob lips.specials.SYMBOL)

(define (frob)
  (let ((lexer lips.__parser__.__lexer__))
    (if (char=? (lexer.peek_char) #\`)
        (begin
          (lexer.skip_char)
          (let loop ((result (vector)) (char (lexer.peek_char)))
            (lexer.skip_char)
            (if (char=? char #\`)
                (result.join "")
                (loop (result.concat char) (lexer.peek_char))))))))

(print #raw`foo \ bar`)