Added alien support, added core library

matthew.willis 2006-08-21 04:35:06 +00:00
parent cefb7829c7
commit bbb53dbfab
6 changed files with 99 additions and 11 deletions

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@ -0,0 +1,65 @@
USING: lazy-lists io strings sequences math namespaces kernel ;
IN: lambda
: lambda-core ( -- expr-string-array )
{
":0 (one.(zero.zero))"
":SUCC (num.(one.(zero.(one((num one) zero)))))"
}
0 lfrom 100 swap ltake list>array
[
[ ":" , dup 1 + number>string , " (SUCC " , number>string ,
")" , ] { } make concat
] map append
0 lfrom 26 swap ltake list>array
[
[ ":" , dup 65 + ch>string , " " , number>string , ] { } make concat
] map append
{
":LF 10"
":FALSE (t.(f.f))"
":TRUE (t.(f.t))"
":ISZERO (num.((num (pred. FALSE)) TRUE))"
":ADD (num.(other.((num SUCC) other)))"
":MULT (num.(other.((num (ADD other)) 0)))"
":PRED (n.(f.(x.(((n (g.(h.(h(g f))))) (u. x)) (u.u)))))"
":SUBFROM (num.(other.((num PRED) other)))"
":FACT (fact.(num.(((ISZERO num) 1) ((MULT num) (fact (PRED num))))))"
":YCOMBINATOR (func.((y. (func (y y)))(y. (func (y y)))))"
":FACTORIAL (YCOMBINATOR FACT)"
":CONS (car.(cdr.(which.((which car) cdr))))"
":CAR (cons.(cons TRUE))"
":CDR (cons.(cons FALSE))"
":PCONS (pcons.(num.(cons.(((ISZERO num) (PRINTSPECIAL LF)) ((PRINTCHAR (CAR cons)) ((pcons (PRED num)) (CDR cons)))))))"
":PRINTCONS (YCOMBINATOR PCONS)"
":NUMTOCHAR (num. ((ADD 48) num))"
":ALPHATOCHAR (num. ((ADD 65) num))"
":PRINTNUM (num.([PRINTCHAR] (ALIENNUM (NUMTOCHAR num))))"
":PRINTCHAR (char.([PRINTCHAR] (ALIENNUM (ALPHATOCHAR char))))"
":PRINTSPECIAL (special.([PRINTCHAR] (ALIENNUM special)))"
":ALIEN0 alienbaseonenum"
":ALIENNUM (num.((num [ALIENSUCC]) ALIEN0))"
":HELLOCONS ((CONS H) ((CONS E) ((CONS Y) nil)))"
":HELLO ((PRINTCONS 3) HELLOCONS)"
"(([HELLO] nil) ([INFO] nil)"
} append ;
: print-return ( -- node )
write "(nil.nil)" lambda-parse second ;
: HELLO ( node -- node )
drop "\nHello and Welcome to Lambda!\n" print-return ;
: INFO ( node -- node )
drop "Type HELLO and wait 10 seconds to see me flex my io muscles.\n" print-return ;
: ALIENSUCC ( node -- node )
variable-node-var "a" append <variable-node> ;
: PRINTCHAR ( node -- node )
#! takes a base one num and prints its char equivalent
variable-node-var length "alienbaseonenum" length - ch>string print-return ;

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@ -1,8 +1,6 @@
Lambda TODO
-----------
Change definition syntax from :<NAME> <EXPR> to <NAME>:<EXPR>
Documentation
Unit tests
More graceful parse error handling
Factor out tree traversing into its own lib
Core library

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@ -29,7 +29,8 @@ IN: lambda
: lambda-boot ( -- names )
#! load the core lambda library
H{ } clone ;
H{ } clone dup lambda-core
[ lambda-parse lambda-eval lambda-print drop ] each-with ;
: (lambda) ( names -- names )
readln dup "." = [ drop ] [

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@ -1,6 +1,7 @@
PROVIDE: lambda {
"nodes.factor"
"parser.factor"
"core.factor"
"lambda.factor"
} {
"test/lambda.factor"

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@ -1,7 +1,7 @@
#! A lambda expression manipulator, by Matthew Willis
REQUIRES: lazy-lists ;
USING: lazy-lists strings arrays hashtables
sequences namespaces words kernel ;
sequences namespaces words parser kernel ;
IN: kernel
: dip swap slip ; inline
@ -11,6 +11,7 @@ IN: lambda
TUPLE: lambda-node expr original canonical ;
TUPLE: apply-node func arg ;
TUPLE: variable-node var ;
TUPLE: alien-node word ;
DEFER: substitute
C: lambda-node ( var expr implicit-empty-lambda-node -- lambda-node )
@ -42,6 +43,8 @@ M: apply-node (traverse) ( data-array word apply-node -- node )
M: variable-node (traverse) ( data-array word variable-node -- node )
(pre) (post) ;
M: alien-node (traverse) ( data-array word alien-node -- node ) nip nip ;
: traverse ( node data-array {pre,post} -- node )
rot (traverse) ;
@ -103,6 +106,12 @@ M: variable-node (substitute) ( data-array variable-node -- node )
: eta-reduce ( lambda-node -- expr )
lambda-node-expr apply-node-func ;
DEFER: evaluate
: alien-reduce ( apply-node -- expr )
#! execute the factor word in the alien-node
dup apply-node-arg evaluate
swap apply-node-func alien-node-word "lambda" lookup execute ;
GENERIC: evaluate
M: lambda-node evaluate ( lambda-node -- node )
#! eta-reduction
@ -119,15 +128,21 @@ M: lambda-node evaluate ( lambda-node -- node )
M: apply-node evaluate ( apply-node -- node )
#! beta-reduction
#! TODO: fix the weird recursion here
dup apply-node-func alien-node?
[ alien-reduce evaluate ]
[
dup apply-node-func lambda-node?
[ beta-reduce evaluate ]
[
dup apply-node-func evaluate swap [ set-apply-node-func ] keep
dup apply-node-func lambda-node? [ evaluate ] when
] if
] if ;
M: variable-node evaluate ( variable-node -- node ) ;
M: alien-node evaluate ( alien-node -- node ) ;
GENERIC: (replace-names)
DEFER: replace-names
M: lambda-node (replace-names) ( names-hash l-node -- node ) nip ;
@ -157,3 +172,6 @@ M: apply-node expr>string ( available-vars apply-node -- string )
M: variable-node expr>string ( available-vars variable-node -- string )
nip variable-node-var dup string? [ lambda-node-canonical ] unless ;
M: alien-node expr>string ( available-vars alien-node -- string )
nip [ "[" , alien-node-word , "]" , ] { } make concat ;

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@ -55,9 +55,14 @@ DEFER: <expr>
"(" token <expr> sp &> <expr> sp <&> ")" token sp <&
[ [ first ] keep second <apply-node> ] <@ ;
: <alien>
#! parses [<FACTOR-WORD>], the alien invocation
#! an alien factor word must be all capital letters and numerals
"[" token <name> sp &> "]" token sp <& [ <alien-node> ] <@ ;
: <expr>
[ <id> call ] [ <lambda> call ] [ <apply> call ] <|> <|>
<name> [ <variable-node> ] <@ <|> ;
<name> [ <variable-node> ] <@ <|> <alien> <|> ;
: <line>
":" token <name> &> <expr> sp <&> f succeed <expr> <&>