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by Edmond 3303 days ago
Are most programming languages really context-sensitive? or aren't they mostly context-free?

My days of fiddling with writing parsers are long ago (https://www.codeproject.com/Articles/7035/A-Java-Language-ID...) but if I remember correctly most languages aim for at most a LL(2) grammar, meaning they are designed so the parser doesn't have to peek more than two tokens ahead before being able to make a correct determination.

1 comments

C has some fun ones:

a * b;

Is either: a times b if a is a var, or declare a varible b with type a. If a is a typedef.

Also:

some_type b = {a, b, c, d};

Is only valid if some_type is an array or a struct. Which is possibly defined elsewhere in the source.

(I tend to see this syntax in some code bases (some_type) { a, b, c, d }, which is a bit better).