Annotation of gforth/stuff.fs, revision 1.40

1.1       anton       1: \ miscelleneous words
                      2: 
1.31      anton       3: \ Copyright (C) 1996,1997,1998,2000,2003 Free Software Foundation, Inc.
1.1       anton       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
1.16      anton      19: \ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
1.1       anton      20: 
1.17      anton      21: require glocals.fs
1.8       anton      22: 
1.6       anton      23: ' require alias needs ( ... "name" -- ... ) \ gforth
1.11      crook      24: \G An alias for @code{require}; exists on other systems (e.g., Win32Forth).
1.1       anton      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 ;
1.2       anton      37: 
1.4       anton      38: \ DMIN and DMAX
                     39: 
1.13      crook      40: : dmin ( d1 d2 -- d ) \ double d-min
1.5       pazsan     41:     2over 2over d> IF  2swap  THEN 2drop ;
1.2       anton      42: 
1.13      crook      43: 
                     44: : dmax ( d1 d2 -- d ) \ double d-max
1.5       pazsan     45:     2over 2over d< IF  2swap  THEN 2drop ;
1.4       anton      46: 
                     47: \ shell commands
                     48: 
1.10      crook      49: 0 Value $? ( -- n ) \ gforth dollar-question
1.12      crook      50: \G @code{Value} -- the exit status returned by the most recently executed
1.9       crook      51: \G @code{system} command.
1.4       anton      52: 
1.14      anton      53: : system ( c-addr u -- ) \ gforth
1.36      anton      54: \G Pass the string specified by @var{c-addr u} to the host operating
                     55: \G system for execution in a sub-shell.  The value of the environment
                     56: \G variable @code{GFORTHSYSTEMPREFIX} (or its default value) is
                     57: \G prepended to the string (mainly to support using @code{command.com}
                     58: \G as shell in Windows instead of whatever shell Cygwin uses by
                     59: \G default; @pxref{Environment variables}).
1.4       anton      60:     (system) throw TO $? ;
1.9       crook      61: 
1.4       anton      62: : sh ( "..." -- ) \ gforth
1.9       crook      63: \G Parse a string and use @code{system} to pass it to the host
                     64: \G operating system for execution in a sub-shell.
1.4       anton      65:     '# parse cr system ;
                     66: 
1.8       anton      67: \ stuff
                     68: 
1.10      crook      69: : ]L ( compilation: n -- ; run-time: -- n ) \ gforth
                     70:     \G equivalent to @code{] literal}
1.8       anton      71:     ] postpone literal ;
                     72: 
1.23      anton      73: [ifundef] in-dictionary?
1.8       anton      74: : in-dictionary? ( x -- f )
                     75:     forthstart dictionary-end within ;
1.23      anton      76: [endif]
1.8       anton      77: 
                     78: : in-return-stack? ( addr -- f )
                     79:     rp0 @ swap - [ forthstart 6 cells + ]L @ u< ;
1.17      anton      80: 
                     81: \ const-does>
                     82: 
                     83: : compile-literals ( w*u u -- ; run-time: -- w*u ) recursive
1.18      anton      84:     \ compile u literals, starting with the bottommost one
1.17      anton      85:     ?dup-if
                     86:        swap >r 1- compile-literals
                     87:        r> POSTPONE literal
                     88:     endif ;
                     89: 
                     90: : compile-fliterals ( r*u u -- ; run-time: -- w*u ) recursive
1.18      anton      91:     \ compile u fliterals, starting with the bottommost one
1.17      anton      92:     ?dup-if
                     93:        { F: r } 1- compile-fliterals
                     94:        r POSTPONE fliteral
                     95:     endif ;
                     96: 
                     97: : (const-does>) ( w*uw r*ur uw ur target "name" -- )
1.18      anton      98:     \ define a colon definition "name" containing w*uw r*ur as
                     99:     \ literals and a call to target.
1.17      anton     100:     { uw ur target }
                    101:     header docol: cfa, \ start colon def without stack junk
                    102:     ur compile-fliterals uw compile-literals
                    103:     target compile, POSTPONE exit reveal ;
                    104: 
1.35      anton     105: : const-does> ( run-time: w*uw r*ur uw ur "name" -- ) \ gforth
                    106:     \G Defines @var{name} and returns.
                    107:     \G  
1.18      anton     108:     \G @var{name} execution: pushes @var{w*uw r*ur}, then performs the
                    109:     \G code following the @code{const-does>}.
1.17      anton     110:     here >r 0 POSTPONE literal
                    111:     POSTPONE (const-does>)
                    112:     POSTPONE ;
                    113:     noname : POSTPONE rdrop
1.32      anton     114:     latestxt r> cell+ ! \ patch the literal
1.17      anton     115: ; immediate
1.19      anton     116: 
1.20      anton     117: \ !! rewrite slurp-file using slurp-fid
1.34      anton     118: : slurp-file ( c-addr1 u1 -- c-addr2 u2 ) \ gforth
1.20      anton     119:     \G @var{c-addr1 u1} is the filename, @var{c-addr2 u2} is the file's contents
1.19      anton     120:     r/o bin open-file throw >r
                    121:     r@ file-size throw abort" file too large"
                    122:     dup allocate throw swap
                    123:     2dup r@ read-file throw over <> abort" could not read whole file"
                    124:     r> close-file throw ;
                    125: 
1.34      anton     126: : slurp-fid { fid -- addr u } \ gforth
1.20      anton     127:     \G @var{addr u} is the content of the file @var{fid}
                    128:     0 0 begin ( awhole uwhole )
                    129:        dup 1024 + dup >r extend-mem ( anew awhole uwhole R: unew )
                    130:        rot r@ fid read-file throw ( awhole uwhole uread R: unew )
                    131:        r> 2dup =
                    132:     while ( awhole uwhole uread unew )
                    133:        2drop
                    134:     repeat
                    135:     - + dup >r resize throw r> ;
1.24      anton     136: 
1.25      anton     137: \ ]] ... [[
                    138: 
                    139: : compile-literal ( n -- )
                    140:     postpone literal ;
                    141: 
                    142: : [[ ( -- )
                    143: \G switch from postpone state to compile state
                    144:     \ this is only a marker; it is never really interpreted
                    145:     compile-only-error ; immediate
                    146: 
                    147: : postponer ( c-addr u -- )
                    148:     2dup find-name dup if ( c-addr u nt )
                    149:        nip nip name>comp
                    150:        2dup [comp'] [[ d= if
                    151:            2drop ['] compiler is parser
                    152:        else
                    153:            postpone,
                    154:        endif
                    155:     else
                    156:        drop
                    157:        2dup snumber? dup if
                    158:            0> IF
                    159:                swap postpone literal postpone compile-literal
                    160:            THEN
                    161:            postpone Literal postpone compile-literal
                    162:            2drop
                    163:        ELSE
                    164:            drop no.extensions
                    165:        THEN
                    166:     then ;
                    167: 
                    168: : ]] ( -- )
                    169:     \ switch into postpone state
                    170:     ['] postponer is parser state on ; immediate restrict
                    171: 
1.26      anton     172: \ f.rdp
                    173: 
1.27      anton     174: : push-right ( c-addr u1 u2 cfill -- )
1.26      anton     175:     \ move string at c-addr u1 right by u2 chars (without exceeding
                    176:     \ the original bound); fill the gap with cfill
1.27      anton     177:     >r over min dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr )
1.26      anton     178:     dup 2swap /string cmove>
                    179:     r> r> r> fill ;
                    180: 
1.27      anton     181: : f>buf-rdp-try { f: rf c-addr ur nd up um1 -- um2 }
                    182:     \ um1 is the mantissa length to try, um2 is the actual mantissa length
                    183:     c-addr ur um1 /string '0 fill
                    184:     rf c-addr um1 represent if { nexp fsign }
1.26      anton     185:        nd nexp + up >=
                    186:        ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if
                    187:            \ fixed-point notation
1.27      anton     188:            c-addr ur beforep nexp - dup { befored } '0 push-right
1.26      anton     189:            c-addr beforep 1- befored min dup { beforez } 0 max bl fill
                    190:            fsign if
                    191:                '- c-addr beforez 1- 0 max + c!
                    192:            endif
1.27      anton     193:            c-addr ur beforep /string 1 '. push-right
                    194:            nexp nd +
1.26      anton     195:        else \ exponential notation
1.27      anton     196:            c-addr ur 1 /string 1 '. push-right
1.26      anton     197:            fsign if
1.27      anton     198:                c-addr ur 1 '- push-right
1.26      anton     199:            endif
                    200:            nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen }
1.27      anton     201:            ur explen - 1- fsign + { mantlen }
                    202:            mantlen 0< if \ exponent too large
1.26      anton     203:                drop c-addr ur '* fill
                    204:            else
                    205:                c-addr ur + 0 explen negate /string move
                    206:            endif
1.27      anton     207:            #>> mantlen
1.26      anton     208:        endif
                    209:     else \ inf or nan
                    210:        if \ negative
1.27      anton     211:            c-addr ur 1 '- push-right
1.26      anton     212:        endif
1.27      anton     213:        drop ur
1.26      anton     214:        \ !! align in some way?
1.27      anton     215:     endif
                    216:     1 max ur min ;
                    217: 
1.29      anton     218: : f>buf-rdp ( rf c-addr +nr +nd +np -- ) \ gforth
1.28      anton     219: \G Convert @i{rf} into a string at @i{c-addr nr}.  The conversion
                    220: \G rules and the meanings of @i{nr nd np} are the same as for
1.27      anton     221: \G @code{f.rdp}.
                    222:     \ first, get the mantissa length, then convert for real.  The
                    223:     \ mantissa length is wrong in a few cases because of different
                    224:     \ rounding; In most cases this does not matter, because the
                    225:     \ mantissa is shorter than expected and the final digits are 0;
                    226:     \ but in a few cases the mantissa gets longer.  Then it is
                    227:     \ conceivable that you will see a result that is rounded too much.
                    228:     \ However, I have not been able to construct an example where this
                    229:     \ leads to an unexpected result.
                    230:     swap 0 max swap 0 max
                    231:     fdup 2over 2over 2 pick f>buf-rdp-try f>buf-rdp-try drop ;
1.26      anton     232: 
1.28      anton     233: : f>str-rdp ( rf +nr +nd +np -- c-addr nr ) \ gforth
                    234: \G Convert @i{rf} into a string at @i{c-addr nr}.  The conversion
                    235: \G rules and the meanings of @i{nr +nd np} are the same as for
1.26      anton     236: \G @code{f.rdp}.  The result in in the pictured numeric output buffer
                    237: \G and will be destroyed by anything destroying that buffer.
1.28      anton     238:     rot holdptr @ 1- 0 rot negate /string ( rf +nd np c-addr nr )
1.26      anton     239:     over holdbuf u< -&17 and throw
                    240:     2tuck 2>r f>buf-rdp 2r> ;
                    241: 
1.28      anton     242: : f.rdp ( rf +nr +nd +np -- ) \ gforth
1.26      anton     243: \G Print float @i{rf} formatted.  The total width of the output is
1.30      anton     244: \G @i{nr}.  For fixed-point notation, the number of digits after the
                    245: \G decimal point is @i{+nd} and the minimum number of significant
                    246: \G digits is @i{np}.  @code{Set-precision} has no effect on
                    247: \G @code{f.rdp}.  Fixed-point notation is used if the number of
                    248: \G siginicant digits would be at least @i{np} and if the number of
                    249: \G digits before the decimal point would fit.  If fixed-point notation
                    250: \G is not used, exponential notation is used, and if that does not
                    251: \G fit, asterisks are printed.  We recommend using @i{nr}>=7 to avoid
                    252: \G the risk of numbers not fitting at all.  We recommend
                    253: \G @i{nr}>=@i{np}+5 to avoid cases where @code{f.rdp} switches to
                    254: \G exponential notation because fixed-point notation would have too
                    255: \G few significant digits, yet exponential notation offers fewer
                    256: \G significant digits.  We recommend @i{nr}>=@i{nd}+2, if you want to
                    257: \G have fixed-point notation for some numbers.  We recommend
                    258: \G @i{np}>@i{nr}, if you want to have exponential notation for all
                    259: \G numbers.
1.26      anton     260:     f>str-rdp type ;
                    261: 
                    262: 0 [if]
                    263: : testx ( rf ur nd up -- )
                    264:     '| emit f.rdp ;
                    265: 
                    266: : test ( -- )
                    267:     -0.123456789123456789e-20
                    268:     40 0 ?do
                    269:        cr
                    270:        fdup 7 3 1 testx
                    271:        fdup 7 3 4 testx
                    272:        fdup 7 3 0 testx
                    273:        fdup 7 7 1 testx
                    274:        fdup 7 5 1 testx
                    275:        fdup 7 0 2 testx
                    276:        fdup 5 2 1 testx
                    277:        fdup 4 2 1 testx
                    278:        fdup 18 8 5 testx
                    279:        '| emit
                    280:        10e f*
                    281:     loop ;
                    282: [then]
1.33      anton     283: 
                    284: : f.s ( -- ) \ gforth f-dot-s
                    285:     \G Display the number of items on the floating-point stack,
                    286:     \G followed by a list of the items; TOS is the right-most item.
                    287:     ." <" fdepth 0 .r ." > " fdepth 0 max maxdepth-.s @ min dup 0 
                    288:     ?DO  dup i - 1- floats fp@ + f@ 16 5 11 f.rdp space LOOP  drop ; 
1.37      anton     289: 
                    290: \ defer stuff
                    291: 
1.39      pazsan    292: [ifundef] defer@ : defer@ >body @ ; [then]
                    293: 
1.37      anton     294: :noname    ' defer@ ;
                    295: :noname    postpone ['] postpone defer@ ;
                    296: interpret/compile: action-of ( interpretation "name" -- xt; compilation "name" -- ; run-time -- xt ) \ gforth
                    297: \G @i{Xt} is the XT that is currently assigned to @i{name}.
                    298: 
                    299: ' action-of
                    300: comp' action-of drop
                    301: interpret/compile: what's ( interpretation "name" -- xt; compilation "name" -- ; run-time -- xt ) \ gforth-obsolete
1.38      anton     302: \G Old name of @code{action-of}
1.40    ! anton     303: 
        !           304: 
        !           305: : typewhite ( addr n -- ) \ gforth
        !           306: \G Like type, but white space is printed instead of the characters.
        !           307:     \ bounds u+do
        !           308:     0 max bounds ?do
        !           309:        i c@ #tab = if \ check for tab
        !           310:            #tab
        !           311:        else
        !           312:            bl
        !           313:        then
        !           314:        emit
        !           315:     loop ;
        !           316: 

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