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Parser defect: number should take priority over abbreviation #25
Description
The reference says:
When the parser encounters a sequence of characters which could represent a symbol, or could represent a number or abbreviation, then the number or abbreviation will take priority.
Currently this means that numbers starting with a period are parsed as meth-name, so e.g. (let decay-rate .05) fails with an "error: unbound symbol 'meth-name'"
This is never helpful, as 05 is not a valid method name.
Activity
fleabitdev commentedon Dec 27, 2020
The parser is working as specified. We imitate Rust's syntax for numbers and strings wherever possible, and in Rust,
.05isn't a valid floating-point literal.Leaving this issue open, because you've raised two good points:
We should definitely try to provide a better error message for incorrect use of the
meth-nameabbreviation.We could consider adopting a more relaxed syntax for floats in GameLisp, compared to Rust. There are a number of pros and cons. It would be more intuitive and convenient, but less consistent, and more difficult to document. It would require us to add a special-case to the parser, to disable the
meth-nameabbreviation for numbers. It would prevent us from adding any syntax like.0which imitates Rust's tuple-indexing syntax.