diff options
Diffstat (limited to 'guix/import/cabal.scm')
-rw-r--r-- | guix/import/cabal.scm | 42 |
1 files changed, 19 insertions, 23 deletions
diff --git a/guix/import/cabal.scm b/guix/import/cabal.scm index fe03c30254..b969197455 100644 --- a/guix/import/cabal.scm +++ b/guix/import/cabal.scm @@ -130,8 +130,17 @@ to the stack." (define (context-stack-clear!) ((context-stack) 'clear!)) -;; Indentation of the line being parsed. -(define current-indentation (make-parameter 0)) +;; Indentation of the line being parsed and that of the previous line. +(define current-indentation* (make-parameter 0)) + +(define previous-indentation (make-parameter 0)) + +(define* (current-indentation #:optional value) + (if value + (begin + (previous-indentation (current-indentation*)) + (current-indentation* value)) + (current-indentation*))) ;; Signal to reprocess the beginning of line, in case we need to close more ;; than one indentation level. @@ -196,27 +205,13 @@ to the stack." (exprs elif-else) : (append $1 (list ($2 '(())))) (elif-else) : (list ($1 '(())))) ;; LALR(1) parsers prefer to be left-recursive, which make if-statements slightly involved. - ;; XXX: This technically allows multiple else statements. - (elif-else (elif-else ELIF tests OCURLY exprs CCURLY) : (lambda (y) ($1 (list (append (list 'if $3 $5) y)))) - (elif-else ELIF tests open exprs close) : (lambda (y) ($1 (list (append (list 'if $3 $5) y)))) - (elif-else ELSE OCURLY exprs CCURLY) : (lambda (y) ($1 (list $4))) - ;; The 'open' token after 'tests' is shifted after an 'exprs' - ;; is found. This is because, instead of 'exprs' a 'OCURLY' - ;; token is a valid alternative. For this reason, 'open' - ;; pushes a <parse-context> with a line indentation equal to - ;; the indentation of 'exprs'. - ;; - ;; Differently from this, without the rule above this - ;; comment, when an 'ELSE' token is found, the 'open' token - ;; following the 'ELSE' would be shifted immediately, before - ;; the 'exprs' is found (because there are no other valid - ;; tokens). The 'open' would therefore create a - ;; <parse-context> with the indentation of 'ELSE' and not - ;; 'exprs', creating an inconsistency. We therefore allow - ;; mixed style conditionals. - (elif-else ELSE open exprs close) : (lambda (y) ($1 (list $4))) + (elif (elif ELIF tests OCURLY exprs CCURLY) : (lambda (y) ($1 (list (append (list 'if $3 $5) y)))) + (elif ELIF tests open exprs close) : (lambda (y) ($1 (list (append (list 'if $3 $5) y)))) ;; Terminating rule. (if-then) : (lambda (y) (append $1 y))) + (elif-else (elif ELSE OCURLY exprs CCURLY) : (lambda (y) ($1 (list $4))) + (elif ELSE open exprs close) : (lambda (y) ($1 (list $4))) + (elif) : $1) (if-then (IF tests OCURLY exprs CCURLY) : (list 'if $2 $4) (IF tests open exprs close) : (list 'if $2 $4)) (tests (TEST OPAREN ID CPAREN) : `(,$1 ,$3) @@ -237,7 +232,7 @@ to the stack." (OPAREN tests CPAREN) : $2) (open () : (context-stack-push! (make-parse-context (context layout) - (current-indentation)))) + (+ 1 (previous-indentation))))) (close (VCCURLY)))) (define (peek-next-line-indent port) @@ -655,7 +650,8 @@ If #f use the function 'port-filename' to obtain it." (let ((cabal-parser (make-cabal-parser))) (parameterize ((cabal-file-name (or file-name (port-filename port) "standard input")) - (current-indentation 0) + (current-indentation* 0) + (previous-indentation 0) (check-bol? #f) (context-stack (make-stack))) (cabal-parser (make-lexer port) (errorp))))) |