--- gforth/kernel/recognizer.fs 2011/10/05 21:02:09 1.3 +++ gforth/kernel/recognizer.fs 2012/06/23 23:20:23 1.20 @@ -1,5 +1,22 @@ \ recognizer-based interpreter 05oct2011py +\ Copyright (C) 2012 Free Software Foundation, Inc. + +\ This file is part of Gforth. + +\ Gforth is free software; you can redistribute it and/or +\ modify it under the terms of the GNU General Public License +\ as published by the Free Software Foundation, either version 3 +\ of the License, or (at your option) any later version. + +\ This program is distributed in the hope that it will be useful, +\ but WITHOUT ANY WARRANTY; without even the implied warranty of +\ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +\ GNU General Public License for more details. + +\ You should have received a copy of the GNU General Public License +\ along with this program. If not, see http://www.gnu.org/licenses/. + \ Recognizer are words that take a string and try to figure out \ what to do with it. I want to separate the parse action from \ the interpret/compile/postpone action, so that recognizers @@ -15,75 +32,87 @@ \ interpret it, compile interpretation semantics \ compile it, compile it as literal. -: recognizer: ( xt1 xt2 xt3 xt4 -- ) Create 2swap swap 2, swap 2, ; +: recognizer: ( xt1 xt2 xt3 -- ) Create rot , swap , , ; -(field) r>int ( r-addr -- addr ) 0 cells , -(field) r>compint ( r-addr -- ) 1 cells , -(field) r>comp ( r-addr -- ) 2 cells , -(field) r>lit ( r-addr -- ) 3 cells , - -:noname ( ... nt -- ) name>int execute ; -:noname ( ... nt -- ) name>int compile, ; -:noname ( ... nt -- ) name>comp execute ; -:noname ( ... nt -- ) postpone Literal ; -recognizer: r:int-table +(field) r>int ( r-addr -- addr ) 0 cells , +(field) r>comp ( r-addr -- addr ) 1 cells , +(field) r>lit ( r-addr -- addr ) 2 cells , + +' no.extensions dup dup Create r:fail A, A, A, + +: lit, ( n -- ) postpone Literal ; +: nt, ( nt -- ) name>comp execute ; +: nt-ex ( nt -- ) + [ cell 1 floats - dup [IF] ] lp+!# [ dup , [THEN] drop ] + r> >l name>int execute @local0 >r lp+ ; + +' nt-ex +' nt, +' lit, +Create r:word rot A, swap A, A, -:noname ( addr u -- nt int-table true | addr u false ) +: word-recognizer ( addr u -- nt r:word | addr u r:fail ) 2dup find-name [ [IFDEF] prelude-mask ] run-prelude [ [THEN] ] dup - IF - nip nip r:int-table true EXIT - THEN ; Constant int-recognizer + IF nip nip r:word ELSE drop r:fail THEN ; ' noop -:noname postpone Literal ; -dup +' lit, dup -recognizer: r:number +Create r:num rot A, swap A, A, ' noop -:noname postpone 2Literal ; -dup +:noname ( n -- ) postpone 2Literal ; dup -recognizer: r:2number +Create r:2num rot A, swap A, A, -:noname ( addr u -- nt int-table true | addr u false ) +\ snumber? should be implemented as recognizer stack + +: num-recognizer ( addr u -- n/d table | addr u r:fail ) 2dup 2>r snumber? dup IF - 2rdrop 0> IF r:2number ELSE r:number THEN true EXIT + 2rdrop 0> IF r:2num ELSE r:num THEN EXIT THEN - drop 2r> false ; Constant num-recognizer - -' no.extensions dup 2dup recognizer: r:fail + drop 2r> r:fail ; \ recognizer stack $10 Constant max-rec# -Variable forth-recognizer max-rec# cells allot : get-recognizers ( rec-addr -- xt1 .. xtn n ) - dup cell+ swap @ dup >r cells bounds ?DO + dup swap @ dup >r cells bounds swap ?DO I @ - cell +LOOP r> ; + cell -LOOP r> ; : set-recognizers ( xt1 .. xtn n rec-addr -- ) over max-rec# u>= abort" Too many recognizers" - 2dup ! swap cells bounds swap ?DO + 2dup ! cell+ swap cells bounds ?DO I ! - cell -LOOP ; + cell +LOOP ; -num-recognizer int-recognizer 2 forth-recognizer set-recognizers +Variable forth-recognizer + +' word-recognizer A, ' num-recognizer A, max-rec# 2 - cells allot +2 forth-recognizer ! +\ ' num-recognizer ' word-recognizer 2 forth-recognizer set-recognizers \ recognizer loop : do-recognizer ( addr u rec-addr -- token table ) dup cell+ swap @ cells bounds ?DO - I perform IF UNLOOP EXIT THEN + I perform dup r:fail <> IF UNLOOP EXIT THEN drop cell +LOOP r:fail ; +\ nested recognizer helper + +\ : nest-recognizer ( addr u -- token table | addr u r:fail ) +\ xxx-recognizer do-recognizer ; + : interpreter-r ( addr u -- ... xt ) forth-recognizer do-recognizer r>int @ ; +' interpreter-r IS parser1 + : compiler-r ( addr u -- ... xt ) forth-recognizer do-recognizer r>comp @ ; @@ -95,3 +124,13 @@ num-recognizer int-recognizer 2 forth-re \G Enter compilation state. ['] compiler-r IS parser1 state on ; +: >int ( token table -- ) r>int perform ; +: >comp ( token table -- ) r>comp perform ; +: >postpone ( token table -- ) + >r r@ r>lit perform r> r>comp @ compile, ; + +: postpone ( "name" -- ) \ core + \g Compiles the compilation semantics of @i{name}. + parse-name forth-recognizer do-recognizer >postpone +; immediate restrict +