X-Git-Url: https://thelambdalab.xyz/gitweb/index.cgi?a=blobdiff_plain;f=src%2Flib.4th;h=68bb77b429a30192a50aca5d95913f5402738a2e;hb=d0d02a9174dd0a8e4e0c37dc2d990d692ee9a73d;hp=ad6a3a55c8ac618e4bc2df4791f31d8bf451a54f;hpb=b27edfb401b367f76756f26be6f139f59c058a83;p=forth.jl.git diff --git a/src/lib.4th b/src/lib.4th index ad6a3a5..68bb77b 100644 --- a/src/lib.4th +++ b/src/lib.4th @@ -1,3 +1,9 @@ +: \ IMMEDIATE + #TIB @ >IN ! +; \ We can now comment! + +\ BASIC DEFINITIONS ---------------------------------------------------------------------- + : / /MOD SWAP DROP ; : MOD /MOD DROP ; : */ -ROT * SWAP / ; @@ -8,7 +14,16 @@ : FALSE 0 ; : NOT 0= ; -: CELLS ; \ Allow for slightly more portable code +\ Translate a number of cells into memory units +\ (in our case 1 cell = 1 memory unit) +: CELLS ; + +\ Since the smallest unit of memory in our system is 64 bits and since strings +\ are stored as arrays of 64 bit integers, the character store/fetch words are +\ just aliases of the standard store/fetch words. +: C! ! ; +: C@ @ ; +: C, , ; : DEPTH PSP@ PSP0 @ - ; @@ -17,23 +32,18 @@ : LITERAL IMMEDIATE ['] LIT , , ; -: ':' [ CHAR : ] LITERAL ; -: ';' [ CHAR ; ] LITERAL ; -: '(' [ CHAR ( ] LITERAL ; -: ')' [ CHAR ) ] LITERAL ; -: '<' [ CHAR < ] LITERAL ; -: '>' [ CHAR > ] LITERAL ; -: '"' [ CHAR " ] LITERAL ; -: 'A' [ CHAR A ] LITERAL ; -: '0' [ CHAR 0 ] LITERAL ; -: '-' [ CHAR - ] LITERAL ; -: '.' [ CHAR . ] LITERAL ; +: CHAR BL WORD 1+ @ ; + +: [CHAR] IMMEDIATE + CHAR + ['] LIT , , +; : CR '\n' emit ; : 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 @@ -45,9 +55,6 @@ , \ compile it ; -: DEBUGON TRUE DEBUG ! ; -: DEBUGOFF FALSE DEBUG ! ; - \ CONTROL STRUCTURES ---------------------------------------------------------------------- : IF IMMEDIATE @@ -206,12 +213,16 @@ : ( IMMEDIATE 1 \ allowed nested parens by keeping track of depth BEGIN - KEY \ read next character - DUP '(' = IF \ open paren? + >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 ELSE - ')' = IF \ close paren? + [CHAR] ) = IF \ close paren? 1- \ depth decreases THEN THEN @@ -283,10 +294,10 @@ ( print the remainder ) DUP 10 < IF - '0' ( decimal digits 0..9 ) + [CHAR] 0 ( decimal digits 0..9 ) ELSE 10 - ( hex and beyond digits A..Z ) - 'A' + [CHAR] A THEN + EMIT @@ -339,7 +350,7 @@ SWAP ( u flag ) IF ( was it negative? print the - character ) - '-' EMIT + [CHAR] - EMIT THEN U. @@ -348,7 +359,7 @@ : . 0 .R SPACE ; : .S ( -- ) - '<' EMIT DEPTH U. '>' EMIT SPACE + [CHAR] < EMIT DEPTH U. [CHAR] > EMIT SPACE PSP0 @ 1+ BEGIN DUP PSP@ 2 - <= @@ -383,11 +394,6 @@ ( STRINGS ---------------------------------------------------------------------- ) -( Since the smallest unit of memory in our system is 64 bits and since strings - are stored as arrays of 64 bit integers, the character store/fetch words are - just aliases of the standard store/fetch words. ) -: C! ! ; -: C@ @ ; ( Block copy, however, is important and novel: ) : CMOVE ( src dest length -- ) @@ -422,7 +428,7 @@ KEY DROP BEGIN KEY ( get next character of the string ) - DUP '"' <> + DUP [CHAR] " <> WHILE C, ( copy character ) REPEAT @@ -436,7 +442,7 @@ KEY DROP BEGIN KEY - DUP '"' <> + DUP [CHAR] " <> WHILE OVER C! ( save next character ) 1+ ( increment address ) @@ -450,14 +456,14 @@ : ." IMMEDIATE ( -- ) [COMPILE] S" ( read the string, and compile LITSTRING, etc. ) - ['] TELL , ( compile the final TELL ) + ['] TYPE , ( compile the final TYPE ) ; : .( KEY DROP BEGIN KEY - DUP ')' = IF + DUP [CHAR] ) = IF DROP ( drop the double quote character ) EXIT ( return from this function ) THEN @@ -465,11 +471,16 @@ 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) ) + BL 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 ) @@ -487,7 +498,7 @@ : VALUE ( n -- ) - WORD HEADER ( make the dictionary entry (the name follows VALUE) ) + BL WORD HEADER ( make the dictionary entry (the name follows VALUE) ) DOCOL , ( append DOCOL ) ['] LIT , ( append the codeword LIT ) , ( append the initial value ) @@ -495,9 +506,9 @@ ; : 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') ) + >PFA ( get a pointer to the first data field (the 'LIT') ) 1+ ( increment to point at the value ) STATE @ IF ( compiling? ) ['] LIT , ( compile LIT ) @@ -510,9 +521,9 @@ ( 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') ) + >PFA ( get a pointer to the first data field (the 'LIT') ) 1+ ( increment to point at the value ) STATE @ IF ( compiling? ) ['] LIT , ( compile LIT ) @@ -588,7 +599,7 @@ ( 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 ) ; @@ -617,7 +628,14 @@ ; : SEE - WORD FIND ( find the dictionary entry to decompile ) + BL WORD 2DUP FIND ( find the dictionary entry to decompile ) + + ?DUP 0= IF + ." Word '" TYPE ." ' not found in dictionary." + EXIT + THEN + + -ROT 2DROP ( 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). ) @@ -638,7 +656,7 @@ DUP >CFA @ CASE DOCOL OF \ Colon definition - ':' EMIT SPACE DUP ID. SPACE + [CHAR] : EMIT SPACE DUP ID. SPACE DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR ENDOF DOVAR OF @@ -658,12 +676,12 @@ ENDCASE ( begin the definition with : NAME [IMMEDIATE] ) - ( ':' EMIT SPACE DUP ID. SPACE + ( [CHAR] : EMIT SPACE DUP ID. SPACE DUP ?IMMEDIATE IF ." IMMEDIATE " THEN CR 4 ) 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 ) @@ -677,11 +695,11 @@ . ( and print it ) ENDOF ['] LITSTRING OF ( is it LITSTRING ? ) - [ CHAR S ] LITERAL EMIT '"' EMIT SPACE ( print S" ) + [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 ) - '"' EMIT SPACE ( finish the string with a final quote ) + 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 ) ENDOF @@ -722,7 +740,7 @@ 1+ ( end start+1 ) REPEAT - ';' EMIT CR + [CHAR] ; EMIT CR 2DROP ( restore stack ) ;