factor/extra/infix/parser/parser.factor

36 lines
1.3 KiB
Factor

! Copyright (C) 2009 Philipp Brüschweiler
! See http://factorcode.org/license.txt for BSD license.
USING: infix.ast infix.tokenizer kernel math peg.ebnf sequences
strings vectors ;
IN: infix.parser
EBNF: parse-infix
Number = . ?[ ast-number? ]?
Identifier = . ?[ string? ]?
Array = Identifier:i "[" Sum:s "]" => [[ i s ast-array boa ]]
Slice1 = Identifier:i "[" Sum?:from ":" Sum?:to "]" => [[ i from to f ast-slice boa ]]
Slice2 = Identifier:i "[" Sum?:from ":" Sum?:to ":" Sum?:step "]" => [[ i from to step ast-slice boa ]]
Slice = Slice1 | Slice2
Function = Identifier:i "(" FunArgs?:a ")" => [[ i a [ V{ } ] unless* ast-function boa ]]
FunArgs = FunArgs:a "," Sum:s => [[ s a push a ]]
| Sum:s => [[ s 1vector ]]
Terminal = ("-"|"+"):op Terminal:term => [[ term op "-" = [ ast-negation boa ] when ]]
| "(" Sum:s ")" => [[ s ]]
| Number | Array | Slice | Function
| Identifier => [[ ast-local boa ]]
Product = Product:p ("**"|"*"|"/"|"%"):op Terminal:term => [[ p term op ast-op boa ]]
| Terminal
Sum = Sum:s ("+"|"-"):op Product:p => [[ s p op ast-op boa ]]
| Product
End = !(.)
Expression = Sum End
;EBNF
: build-infix-ast ( string -- ast )
tokenize-infix parse-infix ;