File:  [gforth] / gforth / stuff.fs
Revision 1.31: download - view: text, annotated - select for diffs
Sun Mar 9 15:16:56 2003 UTC (16 years, 8 months ago) by anton
Branches: MAIN
CVS tags: v0-6-1, v0-6-0, HEAD
updated copyright years

    1: \ miscelleneous words
    2: 
    3: \ Copyright (C) 1996,1997,1998,2000,2003 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: require glocals.fs
   22: 
   23: ' require alias needs ( ... "name" -- ... ) \ gforth
   24: \G An alias for @code{require}; exists on other systems (e.g., Win32Forth).
   25: \ needs is an F-PC name. we will probably switch to 'needs' in the future
   26: 
   27: \ a little more compiler security
   28: 
   29: \ currently not used by Gforth, but maybe by add-ons e.g., the 486asm
   30: AUser CSP
   31: 
   32: : !CSP ( -- )
   33:     sp@ csp ! ;
   34: 
   35: : ?CSP ( -- )
   36:     sp@ csp @ <> -22 and throw ;
   37: 
   38: \ DMIN and DMAX
   39: 
   40: : dmin ( d1 d2 -- d ) \ double d-min
   41:     2over 2over d> IF  2swap  THEN 2drop ;
   42: 
   43: 
   44: : dmax ( d1 d2 -- d ) \ double d-max
   45:     2over 2over d< IF  2swap  THEN 2drop ;
   46: 
   47: \ shell commands
   48: 
   49: 0 Value $? ( -- n ) \ gforth dollar-question
   50: \G @code{Value} -- the exit status returned by the most recently executed
   51: \G @code{system} command.
   52: 
   53: : system ( c-addr u -- ) \ gforth
   54: \G Pass the string specified by @var{c-addr u} to the host operating system
   55: \G for execution in a sub-shell.
   56:     (system) throw TO $? ;
   57: 
   58: : sh ( "..." -- ) \ gforth
   59: \G Parse a string and use @code{system} to pass it to the host
   60: \G operating system for execution in a sub-shell.
   61:     '# parse cr system ;
   62: 
   63: \ stuff
   64: 
   65: : ]L ( compilation: n -- ; run-time: -- n ) \ gforth
   66:     \G equivalent to @code{] literal}
   67:     ] postpone literal ;
   68: 
   69: [ifundef] in-dictionary?
   70: : in-dictionary? ( x -- f )
   71:     forthstart dictionary-end within ;
   72: [endif]
   73: 
   74: : in-return-stack? ( addr -- f )
   75:     rp0 @ swap - [ forthstart 6 cells + ]L @ u< ;
   76: 
   77: \ const-does>
   78: 
   79: : compile-literals ( w*u u -- ; run-time: -- w*u ) recursive
   80:     \ compile u literals, starting with the bottommost one
   81:     ?dup-if
   82: 	swap >r 1- compile-literals
   83: 	r> POSTPONE literal
   84:     endif ;
   85: 
   86: : compile-fliterals ( r*u u -- ; run-time: -- w*u ) recursive
   87:     \ compile u fliterals, starting with the bottommost one
   88:     ?dup-if
   89: 	{ F: r } 1- compile-fliterals
   90: 	r POSTPONE fliteral
   91:     endif ;
   92: 
   93: : (const-does>) ( w*uw r*ur uw ur target "name" -- )
   94:     \ define a colon definition "name" containing w*uw r*ur as
   95:     \ literals and a call to target.
   96:     { uw ur target }
   97:     header docol: cfa, \ start colon def without stack junk
   98:     ur compile-fliterals uw compile-literals
   99:     target compile, POSTPONE exit reveal ;
  100: 
  101: : const-does> ( run-time: w*uw r*ur uw ur "name" -- )
  102:     \G Defines @var{name} and returns.@sp 0
  103:     \G @var{name} execution: pushes @var{w*uw r*ur}, then performs the
  104:     \G code following the @code{const-does>}.
  105:     here >r 0 POSTPONE literal
  106:     POSTPONE (const-does>)
  107:     POSTPONE ;
  108:     noname : POSTPONE rdrop
  109:     lastxt r> cell+ ! \ patch the literal
  110: ; immediate
  111: 
  112: \ !! rewrite slurp-file using slurp-fid
  113: : slurp-file ( c-addr1 u1 -- c-addr2 u2 )
  114:     \G @var{c-addr1 u1} is the filename, @var{c-addr2 u2} is the file's contents
  115:     r/o bin open-file throw >r
  116:     r@ file-size throw abort" file too large"
  117:     dup allocate throw swap
  118:     2dup r@ read-file throw over <> abort" could not read whole file"
  119:     r> close-file throw ;
  120: 
  121: : slurp-fid { fid -- addr u }
  122:     \G @var{addr u} is the content of the file @var{fid}
  123:     0 0 begin ( awhole uwhole )
  124: 	dup 1024 + dup >r extend-mem ( anew awhole uwhole R: unew )
  125: 	rot r@ fid read-file throw ( awhole uwhole uread R: unew )
  126: 	r> 2dup =
  127:     while ( awhole uwhole uread unew )
  128: 	2drop
  129:     repeat
  130:     - + dup >r resize throw r> ;
  131: 
  132: \ ]] ... [[
  133: 
  134: : compile-literal ( n -- )
  135:     postpone literal ;
  136: 
  137: : [[ ( -- )
  138: \G switch from postpone state to compile state
  139:     \ this is only a marker; it is never really interpreted
  140:     compile-only-error ; immediate
  141: 
  142: : postponer ( c-addr u -- )
  143:     2dup find-name dup if ( c-addr u nt )
  144: 	nip nip name>comp
  145: 	2dup [comp'] [[ d= if
  146: 	    2drop ['] compiler is parser
  147: 	else
  148: 	    postpone,
  149: 	endif
  150:     else
  151: 	drop
  152: 	2dup snumber? dup if
  153: 	    0> IF
  154: 		swap postpone literal postpone compile-literal
  155: 	    THEN
  156: 	    postpone Literal postpone compile-literal
  157: 	    2drop
  158: 	ELSE
  159: 	    drop no.extensions
  160: 	THEN
  161:     then ;
  162: 
  163: : ]] ( -- )
  164:     \ switch into postpone state
  165:     ['] postponer is parser state on ; immediate restrict
  166: 
  167: \ f.rdp
  168: 
  169: : push-right ( c-addr u1 u2 cfill -- )
  170:     \ move string at c-addr u1 right by u2 chars (without exceeding
  171:     \ the original bound); fill the gap with cfill
  172:     >r over min dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr )
  173:     dup 2swap /string cmove>
  174:     r> r> r> fill ;
  175: 
  176: : f>buf-rdp-try { f: rf c-addr ur nd up um1 -- um2 }
  177:     \ um1 is the mantissa length to try, um2 is the actual mantissa length
  178:     c-addr ur um1 /string '0 fill
  179:     rf c-addr um1 represent if { nexp fsign }
  180: 	nd nexp + up >=
  181: 	ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if
  182: 	    \ fixed-point notation
  183: 	    c-addr ur beforep nexp - dup { befored } '0 push-right
  184: 	    c-addr beforep 1- befored min dup { beforez } 0 max bl fill
  185: 	    fsign if
  186: 		'- c-addr beforez 1- 0 max + c!
  187: 	    endif
  188: 	    c-addr ur beforep /string 1 '. push-right
  189: 	    nexp nd +
  190: 	else \ exponential notation
  191: 	    c-addr ur 1 /string 1 '. push-right
  192: 	    fsign if
  193: 		c-addr ur 1 '- push-right
  194: 	    endif
  195: 	    nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen }
  196: 	    ur explen - 1- fsign + { mantlen }
  197: 	    mantlen 0< if \ exponent too large
  198: 		drop c-addr ur '* fill
  199: 	    else
  200: 		c-addr ur + 0 explen negate /string move
  201: 	    endif
  202: 	    #>> mantlen
  203: 	endif
  204:     else \ inf or nan
  205: 	if \ negative
  206: 	    c-addr ur 1 '- push-right
  207: 	endif
  208: 	drop ur
  209: 	\ !! align in some way?
  210:     endif
  211:     1 max ur min ;
  212: 
  213: : f>buf-rdp ( rf c-addr +nr +nd +np -- ) \ gforth
  214: \G Convert @i{rf} into a string at @i{c-addr nr}.  The conversion
  215: \G rules and the meanings of @i{nr nd np} are the same as for
  216: \G @code{f.rdp}.
  217:     \ first, get the mantissa length, then convert for real.  The
  218:     \ mantissa length is wrong in a few cases because of different
  219:     \ rounding; In most cases this does not matter, because the
  220:     \ mantissa is shorter than expected and the final digits are 0;
  221:     \ but in a few cases the mantissa gets longer.  Then it is
  222:     \ conceivable that you will see a result that is rounded too much.
  223:     \ However, I have not been able to construct an example where this
  224:     \ leads to an unexpected result.
  225:     swap 0 max swap 0 max
  226:     fdup 2over 2over 2 pick f>buf-rdp-try f>buf-rdp-try drop ;
  227: 
  228: : f>str-rdp ( rf +nr +nd +np -- c-addr nr ) \ gforth
  229: \G Convert @i{rf} into a string at @i{c-addr nr}.  The conversion
  230: \G rules and the meanings of @i{nr +nd np} are the same as for
  231: \G @code{f.rdp}.  The result in in the pictured numeric output buffer
  232: \G and will be destroyed by anything destroying that buffer.
  233:     rot holdptr @ 1- 0 rot negate /string ( rf +nd np c-addr nr )
  234:     over holdbuf u< -&17 and throw
  235:     2tuck 2>r f>buf-rdp 2r> ;
  236: 
  237: : f.rdp ( rf +nr +nd +np -- ) \ gforth
  238: \G Print float @i{rf} formatted.  The total width of the output is
  239: \G @i{nr}.  For fixed-point notation, the number of digits after the
  240: \G decimal point is @i{+nd} and the minimum number of significant
  241: \G digits is @i{np}.  @code{Set-precision} has no effect on
  242: \G @code{f.rdp}.  Fixed-point notation is used if the number of
  243: \G siginicant digits would be at least @i{np} and if the number of
  244: \G digits before the decimal point would fit.  If fixed-point notation
  245: \G is not used, exponential notation is used, and if that does not
  246: \G fit, asterisks are printed.  We recommend using @i{nr}>=7 to avoid
  247: \G the risk of numbers not fitting at all.  We recommend
  248: \G @i{nr}>=@i{np}+5 to avoid cases where @code{f.rdp} switches to
  249: \G exponential notation because fixed-point notation would have too
  250: \G few significant digits, yet exponential notation offers fewer
  251: \G significant digits.  We recommend @i{nr}>=@i{nd}+2, if you want to
  252: \G have fixed-point notation for some numbers.  We recommend
  253: \G @i{np}>@i{nr}, if you want to have exponential notation for all
  254: \G numbers.
  255:     f>str-rdp type ;
  256: 
  257: 0 [if]
  258: : testx ( rf ur nd up -- )
  259:     '| emit f.rdp ;
  260: 
  261: : test ( -- )
  262:     -0.123456789123456789e-20
  263:     40 0 ?do
  264: 	cr
  265: 	fdup 7 3 1 testx
  266: 	fdup 7 3 4 testx
  267: 	fdup 7 3 0 testx
  268: 	fdup 7 7 1 testx
  269: 	fdup 7 5 1 testx
  270: 	fdup 7 0 2 testx
  271: 	fdup 5 2 1 testx
  272: 	fdup 4 2 1 testx
  273: 	fdup 18 8 5 testx
  274: 	'| emit
  275: 	10e f*
  276:     loop ;
  277: [then]

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