Annotation of gforth/quotes.fs, revision 1.3

1.1       anton       1: \ quote: S\" and .\" words
                      2: 
                      3: \ Copyright (C) 2002 Free Software Foundation, Inc.
                      4: 
                      5: \ This file is part of Gforth.
                      6: 
                      7: \ Gforth is free software; you can redistribute it and/or
                      8: \ modify it under the terms of the GNU General Public License
                      9: \ as published by the Free Software Foundation; either version 2
                     10: \ of the License, or (at your option) any later version.
                     11: 
                     12: \ This program is distributed in the hope that it will be useful,
                     13: \ but WITHOUT ANY WARRANTY; without even the implied warranty of
                     14: \ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
                     15: \ GNU General Public License for more details.
                     16: 
                     17: \ You should have received a copy of the GNU General Public License
                     18: \ along with this program; if not, write to the Free Software
                     19: \ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
                     20: 
                     21: : char/ ; immediate
                     22: 
                     23: : parse-num-x  ( c-addr1 base -- c-addr2 c )
                     24:     base !
                     25:     0. rot source chars + over - char/ >number
                     26:     drop rot rot drop ;
                     27: 
                     28: : parse-num ( c-addr1 base -- c-addr2 c )
                     29:     base @ >r
                     30:     ['] parse-num-x catch
                     31:     r> base ! throw ;
                     32: 
                     33: create \-escape-table
                     34:     7 c,        8 c,  char c c,  char d c,      27 c,      12 c,  char g c,
                     35: char h c,  char i c,  char j c,  char k c,  char l c,  char m c,      10 c,
                     36: char o c,  char p c,  char q c,      13 c,  char s c,       8 c,  char u c,
                     37:     11 c,
                     38: 
                     39: : \-escape ( c-addr1 -- c-addr2 c )
                     40:     \ c-addr1 points at a char right after a '\', c-addr2 points right
                     41:     \ after the whole sequence, c is the translated char
1.2       anton      42:     dup c@
                     43:     dup [char] x = if
1.1       anton      44:        drop char+ 16 parse-num exit
                     45:     endif
                     46:     dup [char] 0 [char] 8 within if
                     47:        drop 8 parse-num exit
                     48:     endif
1.2       anton      49:     dup [char] n = if
                     50:        \ \-escapes were designed to translate to one character, so
                     51:        \ this is quite ugly: copy all but the last char right away
                     52:        drop newline 1-
                     53:        2dup here swap chars dup allot move
                     54:        chars + c@
                     55:     else
                     56:        dup [char] a [char] w within if
                     57:            [char] a - chars \-escape-table + c@
                     58:        endif
1.1       anton      59:     endif
                     60:     1 chars under+ ;
                     61: 
                     62: : \"-parse ( "string"<"> -- c-addr u )
                     63: \G parses string, translating @code{\}-escapes to characters (as in
                     64: \G C).  The resulting string resides at @code{here char+}.  The
                     65: \G supported @code{\-escapes} are: @code{\a} BEL (alert), @code{\b}
1.2       anton      66: \G BS, @code{\e} ESC (not in C99), @code{\f} FF, @code{\n} newline,
                     67: \G @code{\r} CR, @code{\t} HT, @code{\v} VT, @code{\"} ",
1.1       anton      68: \G @code{\}[0-7]+ octal numerical character value, @code{\x}[0-9a-f]+
                     69: \G hex numerical character value; a @code{\} before any other
                     70: \G character represents that character (only ', \, ? in C99).
                     71:     here >r 0 c,
                     72:     >in @ chars source chars over + >r + begin ( parse-area R: here parse-end )
                     73:        dup r@ < while
                     74:            dup c@ [char] " <> while
                     75:                dup c@ dup [char] \ = if ( parse-area c R: here parse-end )
                     76:                    drop char+ dup r@ = abort" unfinished \-escape"
                     77:                    \-escape c,
                     78:                else
                     79:                    c, char+
                     80:                endif
                     81:        repeat then
                     82:     char+ source >r - r> min char/ >in !
                     83:     r> drop
                     84:     here r> - dup negate allot
                     85:     here swap char/ 1 /string ;
                     86: 
                     87: :noname \"-parse save-mem ;
                     88: :noname postpone (s") \"-parse dup c, 1+ chars allot drop ;
                     89: interpret/compile: s\" ( compilation 'ccc"' -- ; run-time -- c-addr u )        \ gforth        s-backslash-quote
                     90: \G Like @code{S"}, but translates C-like \-escape-sequences into
                     91: \G single characters.  See @code{\"-parse} for details.
                     92: 
                     93: :noname \"-parse type ;
                     94: :noname postpone (.") \"-parse dup c, 1+ chars allot drop ;
                     95: interpret/compile: .\" ( compilation 'ccc"' -- ; run-time -- ) \ gforth        dot-backslash-quote
                     96: 
1.3     ! anton      97: 0 [if] \ test
1.1       anton      98:     s" 123" drop 10 parse-num-x 123 <> throw drop .s
                     99:     s" 123a" drop 10 parse-num   123 <> throw drop .s
                    100:     s" x1fg" drop \-escape 31 <> throw drop .s
                    101:     s" 00129" drop \-escape 10 <> throw drop .s
                    102:     s" a" drop \-escape 7 <> throw drop .s
                    103:     \"-parse " s" " compare 0<> throw .s
                    104:     \"-parse \a\b\c\e\f\n\r\t\v\100\x40xabcde" dump
1.2       anton     105:     s\" \a\bcd\e\fghijklm\12opq\rs\tu\v" \-escape-table over compare 0<> throw
                    106:     s\" \w\0101\x041\"\\" name wAA"\ compare 0<> throw
1.1       anton     107:     s\" s\\\" \\" ' evaluate catch 0= throw
                    108: [endif]

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