Work around ambiguities in LL(1) assembler parser

Hi,


Writing an assembler, I'm stuck with ambiguities with my syntax. The
syntactic analysis is a simple LL(1) recursive descent parser. Here is
the issue (look at the "(" as a FIRST)


LDA (data),Y ; #1 Indirect address indexed by Y


index EQU 123
LDA (index-1)*3,Y ; #2 Absolute address indexed by Y
LDA 3*(index-1),Y ; Equivalent but non ambiguous


An except of the grammar :


line = mnemonic oper
oper = "(" addr ")" "," "Y"
| addr "," "Y"
addr = ["+"|"-"] term { ["+"|"-"] term }
... etc


The "(" of the _oper_ rule conflicts with the one from the _addr_
expression. Do I get this right ?


Is there a work around ?


Thanks for your time.

Return to the comp.compilers page.
Search the comp.compilers archives again.