factor/core/strings/parser/parser.factor

163 lines
3.8 KiB
Factor

! Copyright (C) 2008, 2009 Slava Pestov, Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors arrays assocs combinators kernel kernel.private
lexer math math.parser namespaces sbufs sequences splitting
strings ;
IN: strings.parser
ERROR: bad-escape char ;
: escape ( escape -- ch )
H{
{ CHAR: a CHAR: \a }
{ CHAR: b CHAR: \b }
{ CHAR: e CHAR: \e }
{ CHAR: f CHAR: \f }
{ CHAR: n CHAR: \n }
{ CHAR: r CHAR: \r }
{ CHAR: t CHAR: \t }
{ CHAR: s CHAR: \s }
{ CHAR: v CHAR: \v }
{ CHAR: \s CHAR: \s }
{ CHAR: 0 CHAR: \0 }
{ CHAR: \\ CHAR: \\ }
{ CHAR: \" CHAR: \" }
} ?at [ bad-escape ] unless ;
SYMBOL: name>char-hook
name>char-hook [
[ "Unicode support not available" throw ]
] initialize
: hex-escape ( str -- ch str' )
2 cut-slice [ hex> ] dip ;
: unicode-escape ( str -- ch str' )
"{" ?head-slice [
CHAR: } over index cut-slice
[ >string name>char-hook get call( name -- char ) ] dip
rest-slice
] [
6 cut-slice [ hex> ] dip
] if ;
: next-escape ( str -- ch str' )
unclip-slice {
{ CHAR: u [ unicode-escape ] }
{ CHAR: x [ hex-escape ] }
[ escape swap ]
} case ;
<PRIVATE
: (unescape-string) ( accum str i/f -- accum )
{ sbuf object object } declare
[
cut-slice [ append! ] dip
rest-slice next-escape [ suffix! ] dip
CHAR: \\ over index (unescape-string)
] [
append!
] if* ;
PRIVATE>
: unescape-string ( str -- str' )
CHAR: \\ over index [
[ [ length <sbuf> ] keep ] dip (unescape-string)
] when* "" like ;
<PRIVATE
: (parse-short-string) ( accum str -- accum m )
{ sbuf slice } declare
dup [ "\"\\" member? ] find [
[ cut-slice [ append! ] dip rest-slice ] dip
CHAR: " = [
from>>
] [
next-escape [ suffix! ] dip (parse-short-string)
] if
] [
"Unterminated string" throw
] if* ;
PRIVATE>
: parse-short-string ( -- str )
SBUF" " clone lexer get [
swap tail-slice (parse-short-string) [ "" like ] dip
] change-lexer-column ;
<PRIVATE
: lexer-subseq ( i lexer -- before )
{ fixnum lexer } declare
[ [ column>> ] [ line-text>> ] bi swapd subseq ]
[ column<< ] 2bi ;
: rest-of-line ( lexer -- seq )
{ lexer } declare
[ line-text>> ] [ column>> ] bi tail-slice ;
: current-char ( lexer -- ch/f )
{ lexer } declare
[ column>> ] [ line-text>> ] bi ?nth ;
: advance-char ( lexer -- )
{ lexer } declare
[ 1 + ] change-column drop ;
: next-char ( lexer -- ch/f )
{ lexer } declare
dup still-parsing-line? [
[ current-char ] [ advance-char ] bi
] [
drop f
] if ;
: next-line% ( accum lexer -- )
{ sbuf lexer } declare
[ rest-of-line swap push-all ] [ next-line ] bi ;
: find-next-token ( lexer -- i elt )
{ lexer } declare
[ column>> ] [ line-text>> ] bi
[ "\"\\" member? ] find-from ;
DEFER: (parse-full-string)
: parse-found-token ( accum lexer i elt -- )
{ sbuf lexer fixnum fixnum } declare
[ over lexer-subseq pick push-all ] dip
CHAR: \ = [
dup dup [ next-char ] bi@
[ [ pick push ] bi@ ]
[ drop 2dup next-line% ] if*
(parse-full-string)
] [
advance-char drop
] if ;
: (parse-full-string) ( accum lexer -- )
{ sbuf lexer } declare
dup still-parsing? [
dup find-next-token [
parse-found-token
] [
drop 2dup next-line%
CHAR: \n pick push
(parse-full-string)
] if*
] [
throw-unexpected-eof
] if ;
PRIVATE>
: parse-full-string ( -- str )
SBUF" " clone [
lexer get (parse-full-string)
] keep unescape-string ;