Divided up library code.

[forth.jl.git] / src / lib_1_basic.4th

diff --git a/src/lib_1_basic.4th b/src/lib_1_basic.4th
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+\ Basic definitions
+
+: / /MOD SWAP DROP ;
+: MOD /MOD DROP ;
+: */ -ROT * SWAP / ;
+
+: NEGATE \ ( x -- -x )
+    0 SWAP - ;
+
+: NIP \ ( x y -- y )
+    SWAP DROP ;
+
+: TUCK \ ( x y -- y x y )
+    DUP -ROT ;
+
+: PICK \ ( x_u ... x_1 x_0 u -- x_u ... x_1 x_0 x_u )
+        1+ PSP@ SWAP - @ ;
+
+: TRUE -1 ;
+: FALSE 0 ;
+: NOT 0= ;
+
+\ Standard words for manipulating BASE.
+: DECIMAL   10 BASE ! ;
+: HEX       16 BASE ! ;
+
+
+\ 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 - ;
+
+: '\n' 10 ;
+: BL 32 ;
+
+: LITERAL IMMEDIATE ['] LIT , , ;
+
+: ' BL WORD FIND DROP ;
+
+: CHAR BL WORD 1+ @ ;
+: [CHAR] IMMEDIATE
+    CHAR
+    ['] LIT , ,
+;
+
+: CR '\n' emit ;
+: SPACE BL emit ;
+
+: [COMPILE] IMMEDIATE
+        BL WORD         \ get the next word
+        FIND DROP       \ find it in the dictionary
+        ,               \ and compile that
+;
+
+: RECURSE IMMEDIATE
+        LATEST @        \ LATEST points to the word being compiled at the moment
+        >CFA            \ get the codeword
+        ,               \ compile it
+;
+