--- gforth/stuff.fs 2002/08/12 16:39:34 1.21 +++ gforth/stuff.fs 2003/01/25 13:44:54 1.27 @@ -66,8 +66,10 @@ AUser CSP \G equivalent to @code{] literal} ] postpone literal ; +[ifundef] in-dictionary? : in-dictionary? ( x -- f ) forthstart dictionary-end within ; +[endif] : in-return-stack? ( addr -- f ) rp0 @ swap - [ forthstart 6 cells + ]L @ u< ; @@ -127,9 +129,147 @@ AUser CSP repeat - + dup >r resize throw r> ; -: str= ( c-addr1 u1 c-addr2 u2 -- f ) - compare 0= ; +\ ]] ... [[ -: string-prefix? ( c-addr1 u1 c-addr2 u2 -- f ) - \G Is @var{c-addr2 u2} a prefix of @var{c-addr1 u1}? - tuck 2>r min 2r> compare 0= ; +: compile-literal ( n -- ) + postpone literal ; + +: [[ ( -- ) +\G switch from postpone state to compile state + \ this is only a marker; it is never really interpreted + compile-only-error ; immediate + +: postponer ( c-addr u -- ) + 2dup find-name dup if ( c-addr u nt ) + nip nip name>comp + 2dup [comp'] [[ d= if + 2drop ['] compiler is parser + else + postpone, + endif + else + drop + 2dup snumber? dup if + 0> IF + swap postpone literal postpone compile-literal + THEN + postpone Literal postpone compile-literal + 2drop + ELSE + drop no.extensions + THEN + then ; + +: ]] ( -- ) + \ switch into postpone state + ['] postponer is parser state on ; immediate restrict + +\ f.rdp + +: push-right ( c-addr u1 u2 cfill -- ) + \ move string at c-addr u1 right by u2 chars (without exceeding + \ the original bound); fill the gap with cfill + >r over min dup >r rot dup >r ( u1 u2 c-addr R: cfill u2 c-addr ) + dup 2swap /string cmove> + r> r> r> fill ; + +: f>buf-rdp-try { f: rf c-addr ur nd up um1 -- um2 } + \ um1 is the mantissa length to try, um2 is the actual mantissa length + c-addr ur um1 /string '0 fill + rf c-addr um1 represent if { nexp fsign } + nd nexp + up >= + ur nd - 1- dup { beforep } fsign + nexp 0 max >= and if + \ fixed-point notation + c-addr ur beforep nexp - dup { befored } '0 push-right + c-addr beforep 1- befored min dup { beforez } 0 max bl fill + fsign if + '- c-addr beforez 1- 0 max + c! + endif + c-addr ur beforep /string 1 '. push-right + nexp nd + + else \ exponential notation + c-addr ur 1 /string 1 '. push-right + fsign if + c-addr ur 1 '- push-right + endif + nexp 1- s>d tuck dabs <<# #s rot sign 'E hold #> { explen } + ur explen - 1- fsign + { mantlen } + mantlen 0< if \ exponent too large + drop c-addr ur '* fill + else + c-addr ur + 0 explen negate /string move + endif + #>> mantlen + endif + else \ inf or nan + if \ negative + c-addr ur 1 '- push-right + endif + drop ur + \ !! align in some way? + endif + 1 max ur min ; + +: f>buf-rdp ( rf c-addr ur nd up -- ) \ gforth +\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion +\G rules and the meanings of @i{ur nd up} are the same as for +\G @code{f.rdp}. + \ first, get the mantissa length, then convert for real. The + \ mantissa length is wrong in a few cases because of different + \ rounding; In most cases this does not matter, because the + \ mantissa is shorter than expected and the final digits are 0; + \ but in a few cases the mantissa gets longer. Then it is + \ conceivable that you will see a result that is rounded too much. + \ However, I have not been able to construct an example where this + \ leads to an unexpected result. + swap 0 max swap 0 max + fdup 2over 2over 2 pick f>buf-rdp-try f>buf-rdp-try drop ; + +: f>str-rdp ( rf ur +nd up -- c-addr ur ) \ gforth +\G Convert @i{rf} into a string at @i{c-addr ur}. The conversion +\G rules and the meanings of @i{ur +nd up} are the same as for +\G @code{f.rdp}. The result in in the pictured numeric output buffer +\G and will be destroyed by anything destroying that buffer. + rot holdptr @ 1- 0 rot negate /string ( rf +nd up c-addr ur ) + over holdbuf u< -&17 and throw + 2tuck 2>r f>buf-rdp 2r> ; + +: f.rdp ( rf ur +nd up -- ) \ gforth +\G Print float @i{rf} formatted. The total width of the output is +\G @i{nr}, the number of digits after the decimal point is @i{+nd}, +\G the minimum number of significant digits for fixed-point notation +\G is @i{up}. @code{Set-precision} has no effect on @code{f.rdp}. +\G Fixed-point notation is used if the number of siginicant digits +\G would be larger than @i{up} and if the number of digits before the +\G decimal point would fit. If fixed-point notation is not used, +\G exponential notation is used, and if that does not fit, asterisks +\G are printed. We recommend using @i{ur}>=7 to avoid the risk of +\G numbers not fitting at all. We recommend @i{ur}>=@i{up}+5 to avoid +\G cases where @code{f.rdp} switches to exponential notation because +\G fixed-point notation would have too few significant digits, yet +\G exponential notation offers fewer significant digits. We recomment +\G @i{ur}>=@i{nd}+2, if you want to have fixed-point notation for some +\G numbers. + f>str-rdp type ; + +0 [if] +: testx ( rf ur nd up -- ) + '| emit f.rdp ; + +: test ( -- ) + -0.123456789123456789e-20 + 40 0 ?do + cr + fdup 7 3 1 testx + fdup 7 3 4 testx + fdup 7 3 0 testx + fdup 7 7 1 testx + fdup 7 5 1 testx + fdup 7 0 2 testx + fdup 5 2 1 testx + fdup 4 2 1 testx + fdup 18 8 5 testx + '| emit + 10e f* + loop ; +[then]