sounds about right -- finding the appropriate mux point to pinch is indeed the
first step towards sanity. if you get funding, give me a buzz. otherwise, i
will continue to work w/ (old) librx and approach the problem from the guile
perspective. (e.g., below is lex.test w/ a simple shell-lexer spec. probably
guile will be able to do a busybox-like sumo move on the auto* tools by end of
1.4.x.)
the broader social hack is going to be difficult, if anything. people don't
like to reflect because the image they see (initially) is one of incompetence
and foolishness. it takes fortitude to synthesize that stark realization into
actions that support their ideals (and self-image). much easier to deny the
proper place of reflection entirely, along w/ its past implication and future
consequence. ah, children w/ magic wands...
given this, probably the best you can do is to write analysis tools that help
people migrate from the pre- to the fully-muxed state. (i see "autoupdate" is
a step in this direction.) M-x refactor-build-flow, you know.
thi
__________________________________________________
#!/bin/sh
exec ${GUILE-guile} -s $0 "$@" # -*- scheme -*-
!#
;;; Commentary:
;; Usage: $(INST_TESTS_ENVIRONMENT) $(srcdir)/lex.test
;;
;; Basically, we construct a lexer on ourselves; do not modify
;; anything above the commentary line w/o also modifying the
;; associated values in `expected' below!
;;; Code:
(use-modules (lang lex))
;; simple references
lexeme-reader
lexer-regexp-and-handler
make-lexer
eof-token?
;; from comment
(define r (regcomp "if[[:cut 1:]]\\|else[[:cut 2:]]"))
(or (equal? (regexec r "if" '(#\c 0)) '(1 "if"))
(error "'(#\c 0) on \"if\" failed"))
(or (equal? (regexec r "else" '(#\c 0)) '(2 "else"))
(error "'(#\c 0) on \"else\" failed"))
;; from comment using make-lexer
(define ifelse-lexer (make-lexer '(("if" if) ("else" else))))
;; self lexing -- incomplete spec for testing purposes only
(define (token->number token . port) (list 'number (string->number token)))
(define (token->id token . port) (list 'identifier (string->symbol token)))
(define shell-script-lexer-spec
`(("[0-9]\\+" ,token->number)
("/\\([a-zA-Z0-9,=_-]\\+/*\\)*" filename)
("\"\\$@\"" ,(lambda ignored '(dollar-at)))
("\\$" ,(lambda ignored '(dollar)))
("{" ,(lambda ignored '(left-curly)))
("}" ,(lambda ignored '(right-curly)))
("exec" ,(lambda ignored '(exec)))
("#!" ,(lambda ignored '(hash-bang)))
("!#" ,(lambda ignored '(bang-hash)))
("[A-Za-z0-9_][A-Za-z0-9_]*" identifier)
("-" ,(lambda ignored '(dash)))
("\n" ,(lambda ignored '(newline)))
("#[^!][^\n]*" comment)
("." ignored)))
(define shell-script-lexer (make-lexer shell-script-lexer-spec))
(or (procedure? shell-script-lexer)
(error (format #f "not a procedure: ~S" shell-script-lexer)))
(use-modules (ice-9 lineio))
(define p (make-line-buffering-input-port
(open-input-file (car (command-line)))))
(or (lineio-port? p)
(error (format #f "not a lineio port: ~S" p)))
(define expected
'((hash-bang)
(filename "/bin/sh")
(newline)
(exec)
(dollar)
(left-curly)
(identifier "GUILE")
(dash)
(identifier "guile")
(right-curly)
(dash)
(identifier "s")
(dollar)
(number 0)
(dollar-at)
(comment "# -*- scheme -*-")
(newline)
(bang-hash)
(newline)))
(define expected-length (length expected))
(define (next)
(shell-script-lexer p))
(let loop ((lexeme (next)) (check 0))
;;(format #t "~S\n" lexeme)
(cond ((eq? '<eoi> (car lexeme)))
((eq? 'ignored (car lexeme))
(loop (next) check))
((and (< check expected-length)
(not (equal? (list-ref expected check)
lexeme)))
(error (format #f "expected ~S but got ~S !!!\n"
(list-ref expected check)
lexeme)))
(else
(loop (next) (1+ check)))))
;;; lex.test ends here
