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Fix grammar not being able to disambiguate some instructions

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When two identifiers follow eachother it could be two instruction
mnemonics or one instruction mnemonic and one operand. To fix this
TOKEN_NEWLINE has been reintroduced as a semantic token. The grammar has
been changed to allow empty statements and every instruction and
directive has to end in a newline. Labels do not have to end in a
newline.

In addition to updating the grammar, the implementation of tokenlist,
ast and parser has been updated to reflect these changes.
This commit is contained in:
omicron
2025-04-16 12:34:44 +02:00
parent 1574ec6249
commit 242fd9baa5
7 changed files with 18 additions and 8 deletions
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6
doc/parser_grammar.txt
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@ -1,13 +1,13 @@
<program> ::= <statement>*
<statement> ::= <label> | <directive> | <instruction>
<statement> ::= <label> | <directive> | <instruction> | <newline>
<label> ::= <identifier> <colon>
<directive> ::= <dot> <section_directive>
<directive> ::= <dot> <section_directive> <newline>
<section_directive> ::= "section" <identifier>
<instruction> ::= <identifier> <operands>
<instruction> ::= <identifier> <operands> <newline>
<operands> ::= <operand> ( <comma> <operand> )*