X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?p=forth.jl.git;a=blobdiff_plain;f=src%2Flib.4th;h=2312aeb1727ca682657c07e0d484dfb5eb7c7386;hp=955cadfe236e34a1c286d4e98c9f5659b5245676;hb=b593ff258f6b62e7bd7c00b566d8f4f812b0f95a;hpb=d2b2b3e5b33f882c18c9e7cf8c6623f4e863c2dd diff --git a/src/lib.4th b/src/lib.4th index 955cadf..2312aeb 100644 --- a/src/lib.4th +++ b/src/lib.4th @@ -1,6 +1,5 @@ : \ IMMEDIATE - KEY - 10 = 0BRANCH [ -5 , ] + #TIB @ >IN ! ; \ We can now comment! \ BASIC DEFINITIONS ---------------------------------------------------------------------- @@ -26,13 +25,16 @@ : C@ @ ; : C, , ; -: DEPTH PSP@ PSP0 @ - ; +: DEPTH PSP@ PSP0 - ; : '\n' 10 ; : BL 32 ; : LITERAL IMMEDIATE ['] LIT , , ; +: ' BL WORD FIND >CFA ; + +: CHAR BL WORD 1+ @ ; : [CHAR] IMMEDIATE CHAR ['] LIT , , @@ -42,7 +44,7 @@ : SPACE BL emit ; : [COMPILE] IMMEDIATE - WORD \ get the next word + BL WORD \ get the next word FIND \ find it in the dictionary >CFA \ get its codeword , \ and compile that @@ -54,61 +56,58 @@ , \ compile it ; -: DEBUGON TRUE DEBUG ! ; -: DEBUGOFF FALSE DEBUG ! ; - \ CONTROL STRUCTURES ---------------------------------------------------------------------- : IF IMMEDIATE ['] 0BRANCH , \ compile 0BRANCH - HERE @ \ save location of the offset on the stack + HERE \ save location of the offset on the stack 0 , \ compile a dummy offset ; : THEN IMMEDIATE DUP - HERE @ SWAP - \ calculate the offset from the address saved on the stack + HERE SWAP - \ calculate the offset from the address saved on the stack SWAP ! \ store the offset in the back-filled location ; : ELSE IMMEDIATE ['] BRANCH , \ definite branch to just over the false-part - HERE @ \ save location of the offset on the stack + HERE \ save location of the offset on the stack 0 , \ compile a dummy offset SWAP \ now back-fill the original (IF) offset DUP \ same as for THEN word above - HERE @ SWAP - + HERE SWAP - SWAP ! ; : BEGIN IMMEDIATE - HERE @ \ save location on the stack + HERE \ save location on the stack ; : UNTIL IMMEDIATE ['] 0BRANCH , \ compile 0BRANCH - HERE @ - \ calculate the offset from the address saved on the stack + HERE - \ calculate the offset from the address saved on the stack , \ compile the offset here ; : AGAIN IMMEDIATE ['] BRANCH , \ compile BRANCH - HERE @ - \ calculate the offset back + HERE - \ calculate the offset back , \ compile the offset here ; : WHILE IMMEDIATE ['] 0BRANCH , \ compile 0BRANCH - HERE @ \ save location of the offset2 on the stack + HERE \ save location of the offset2 on the stack 0 , \ compile a dummy offset2 ; : REPEAT IMMEDIATE ['] BRANCH , \ compile BRANCH SWAP \ get the original offset (from BEGIN) - HERE @ - , \ and compile it after BRANCH + HERE - , \ and compile it after BRANCH DUP - HERE @ SWAP - \ calculate the offset2 + HERE SWAP - \ calculate the offset2 SWAP ! \ and back-fill it in the original location ; @@ -120,15 +119,15 @@ : DO IMMEDIATE ['] LIT , -1 , [COMPILE] IF ['] >R , ['] >R , - ['] LIT , HERE @ 0 , ['] >R , - HERE @ + ['] LIT , HERE 0 , ['] >R , + HERE ; : ?DO IMMEDIATE ['] 2DUP , ['] - , [COMPILE] IF ['] >R , ['] >R , - ['] LIT , HERE @ 0 , ['] >R , - HERE @ + ['] LIT , HERE 0 , ['] >R , + HERE ; : I RSP@ 3 - @ ; @@ -138,7 +137,7 @@ : ?LEAVE IMMEDIATE ['] 0BRANCH , 13 , ['] R> , ['] RDROP , ['] RDROP , - ['] LIT , HERE @ 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! , + ['] LIT , HERE 7 + , ['] DUP , ['] -ROT , ['] - , ['] SWAP , ['] ! , ['] BRANCH , 0 , ; @@ -149,6 +148,7 @@ ; : +LOOP IMMEDIATE + ['] DUP , \ Store copy of increment ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] R> , ['] SWAP , ['] + , ['] 2DUP , ['] - , @@ -162,13 +162,13 @@ [COMPILE] THEN \ Branch back to begining of loop kernel - ['] 0BRANCH , HERE @ - , + ['] 0BRANCH , HERE - , \ Clean up ['] RDROP , ['] RDROP , ['] RDROP , \ Record address of loop end for any LEAVEs to use - HERE @ SWAP ! + HERE SWAP ! [COMPILE] ELSE ['] 2DROP , \ Clean up if loop was entirely skipped (?DO) @@ -215,7 +215,11 @@ : ( IMMEDIATE 1 \ allowed nested parens by keeping track of depth BEGIN - KEY \ read next character + >IN @ #TIB @ >= IF \ End of TIB? + QUERY \ Get next line + THEN + + TIB >IN @ + @ 1 >IN +! DUP [CHAR] ( = IF \ open paren? DROP \ drop the open paren 1+ \ depth increases @@ -358,7 +362,7 @@ : .S ( -- ) [CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE - PSP0 @ 1+ + PSP0 1+ BEGIN DUP PSP@ 2 - <= WHILE @@ -414,53 +418,67 @@ ( C, appends a byte to the current compiled word. ) : C, - HERE @ C! - 1 HERE +! + HERE C! + 1 H +! ; : S" IMMEDIATE ( -- addr len ) STATE @ IF ( compiling? ) ['] LITSTRING , ( compile LITSTRING ) - HERE @ ( save the address of the length word on the stack ) + HERE ( save the address of the length word on the stack ) 0 , ( dummy length - we don't know what it is yet ) - KEY DROP + BEGIN - KEY ( get next character of the string ) + >IN @ #TIB @ >= IF \ End of TIB? + QUERY \ Get next line + THEN + + TIB >IN @ + @ 1 >IN +! \ Get char from TIB + DUP [CHAR] " <> WHILE C, ( copy character ) REPEAT DROP ( drop the double quote character at the end ) DUP ( get the saved address of the length word ) - HERE @ SWAP - ( calculate the length ) + HERE SWAP - ( calculate the length ) 1- ( subtract 1 (because we measured from the start of the length word) ) SWAP ! ( and back-fill the length location ) ELSE ( immediate mode ) - HERE @ ( get the start address of the temporary space ) - KEY DROP + HERE ( get the start address of the temporary space ) + BEGIN - KEY + >IN @ #TIB @ >= IF \ End of TIB? + QUERY \ Get next line + THEN + + TIB >IN @ + @ 1 >IN +! \ Get char from TIB + DUP [CHAR] " <> WHILE OVER C! ( save next character ) 1+ ( increment address ) REPEAT DROP ( drop the final " character ) - HERE @ - ( calculate the length ) - HERE @ ( push the start address ) + HERE - ( calculate the length ) + HERE ( push the start address ) SWAP ( addr len ) THEN ; : ." IMMEDIATE ( -- ) [COMPILE] S" ( read the string, and compile LITSTRING, etc. ) - ['] TELL , ( compile the final TELL ) + ['] TYPE , ( compile the final TYPE ) ; : .( - KEY DROP BEGIN - KEY + >IN @ #TIB @ >= IF \ End of TIB? + QUERY \ Get next line + THEN + + TIB >IN @ + @ 1 >IN +! \ Get char from TIB + DUP [CHAR] ) = IF DROP ( drop the double quote character ) EXIT ( return from this function ) @@ -469,19 +487,21 @@ AGAIN ; +( Converts address of counted string into address of + start of string and length of string. ) +: COUNT ( addr1 -- addr2 n ) + DUP 1+ SWAP @ ; + ( CONSTANTS AND VARIABLES ------------------------------------------------------ ) : CONSTANT - WORD HEADER ( make dictionary entry (the name follows CONSTANT) ) - DOCOL , ( append DOCOL (the codeword field of this word) ) - ['] LIT , ( append the codeword LIT ) - , ( append the value on the top of the stack ) - ['] EXIT , ( append the codeword EXIT ) + CREATE , +DOES> @ ; : ALLOT ( n -- ) - HERE +! ( adds n to HERE, after this the old value of HERE is still on the stack ) + H +! ( adds n to H, after this the old value of H is still on the stack ) ; : VARIABLE @@ -489,20 +509,15 @@ 1 CELLS ALLOT ( allocate 1 cell of memory, push the pointer to this memory ) ; - : VALUE ( n -- ) - WORD HEADER ( make the dictionary entry (the name follows VALUE) ) - DOCOL , ( append DOCOL ) - ['] LIT , ( append the codeword LIT ) - , ( append the initial value ) - ['] EXIT , ( append the codeword EXIT ) + CREATE , +DOES> @ ; : TO IMMEDIATE ( n -- ) - WORD ( get the name of the value ) + BL WORD ( get the name of the value ) FIND ( look it up in the dictionary ) - >DFA ( get a pointer to the first data field (the 'LIT') ) - 1+ ( increment to point at the value ) + >PFA ( get a pointer to the first data field (the 'LIT') ) STATE @ IF ( compiling? ) ['] LIT , ( compile LIT ) , ( compile the address of the value ) @@ -514,10 +529,9 @@ ( x +TO VAL adds x to VAL ) : +TO IMMEDIATE - WORD ( get the name of the value ) + BL WORD ( get the name of the value ) FIND ( look it up in the dictionary ) - >DFA ( get a pointer to the first data field (the 'LIT') ) - 1+ ( increment to point at the value ) + >PFA ( get a pointer to the first data field (the 'LIT') ) STATE @ IF ( compiling? ) ['] LIT , ( compile LIT ) , ( compile the address of the value ) @@ -592,9 +606,9 @@ ( FORGET ---------------------------------------------------------------------- ) : FORGET - WORD FIND ( find the word, gets the dictionary entry address ) + BL WORD FIND ( find the word, gets the dictionary entry address ) DUP @ LATEST ! ( set LATEST to point to the previous word ) - HERE ! ( and store HERE with the dictionary address ) + H ! ( and store H with the dictionary address ) ; ( DUMP ------------------------------------------------------------------------ ) @@ -621,11 +635,18 @@ ; : SEE - WORD FIND ( find the dictionary entry to decompile ) + BL WORD DUP FIND ( find the dictionary entry to decompile ) + + ?DUP 0= IF + ." Word '" COUNT TYPE ." ' not found in dictionary." + EXIT + THEN + + SWAP DROP ( Now we search again, looking for the next word in the dictionary. This gives us the length of the word that we will be decompiling. (Well, mostly it does). ) - HERE @ ( address of the end of the last compiled word ) + HERE ( address of the end of the last compiled word ) LATEST @ ( word last curr ) BEGIN 2 PICK ( word last curr word ) @@ -667,7 +688,7 @@ 4 SPACES - >DFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data ) + >PFA ( get the data address, ie. points after DOCOL | end-of-word start-of-data ) ( now we start decompiling until we hit the end of the word ) BEGIN ( end start ) @@ -684,7 +705,7 @@ [CHAR] S EMIT [CHAR] " EMIT SPACE ( print S" ) 1+ DUP @ ( get the length word ) SWAP 1+ SWAP ( end start+1 length ) - 2DUP TELL ( print the string ) + 2DUP TYPE ( print the string ) [CHAR] " EMIT SPACE ( finish the string with a final quote ) + ( end start+1+len, aligned ) 1- ( because we're about to add 4 below ) @@ -735,4 +756,4 @@ ( MEMORY ------------------------------------------------------------------ ) : UNUSED ( -- cells ) - MEMSIZE HERE @ - ; + MEMSIZE HERE - ;