Parser: error on duplicate case when condition #5036
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| @@ -3992,7 +4034,7 @@ module Crystal | |||
| end | |||
| when :"{" | |||
| return nil unless allow_curly | |||
| when :CHAR, :STRING, :DELIMITER_START, :STRING_ARRAY_START, :SYMBOL_ARRAY_START, :NUMBER, :IDENT, :SYMBOL, :INSTANCE_VAR, :CLASS_VAR, :CONST, :GLOBAL, :"$~", :"$?", :GLOBAL_MATCH_DATA_INDEX, :REGEX, :"(", :"!", :"[", :"[]", :"+", :"-", :"~", :"&", :"->", :"{{", :__LINE__, :__END_LINE__, :__FILE__, :__DIR__, :UNDERSCORE | |||
| when :CHAR, :STRING, :DELIMITER_START, :STRING_ARRAY_START, :SYMBOL_ARRAY_START, :NUMBER, :IDENT, :SYMBOL, :INSTANCE_VAR, :CLASS_VAR, :CONST, :GLOBAL, :"$~", :"$?", :GLOBAL_MATCH_DATA_INDEX, :REGEX, :"(", :"!", :"[", :"[]", :"~", :"->", :"{{", :__LINE__, :__END_LINE__, :__FILE__, :__DIR__, :UNDERSCORE | |||
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It removes duplicate cases...
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Ooooh yes of course, didn't checked the lines above, I thought the other cases where in the same line ><
| when_exp_constant?(exp.value) | ||
| when RangeLiteral | ||
| when_exp_constant?(exp.from) && | ||
| when_exp_constant?(exp.to) |
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We need to test ranges at all (intersection with other values and ranges).
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What do you mean? Here I just check that both ends are "constants" as well. The check for duplicates is in the includes? call in add_when_exp.
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when 5..10
when 8
when 7..11afaiu, all of these cases intersect and should be disallowed together.
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It works for me. 5..10, 6 and 7..11 are all different AST nodes, so the duplicate error won't trigger.
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But they should trigger error.
Anyway when you enables these intersections, you must to check {from, to} as single value instead of two separated.
when 2..5
when 3..5
when 2..4will fail now afaiu.
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Oh, I see what you mean. This change is just about detecting duplicates, what you ask is much more complex. Maybe it can be done for simple ranges like this, but we can do it in a separate PR.
Did you try that code? It compiles fine. I don't understand why you say it will fail now.
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I was wrong, you are right here. But yes, intersection checks should be applied, but it's subject of another PR.
| when_conds << parse_when_expression(cond) | ||
| exp = parse_when_expression(cond) | ||
| when_conds << exp | ||
| add_when_exp(when_exps, exp) |
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when_conds << exp shouldn't be done here, as it would cause a raise in add_when_exp. if when_exps.includes?(exp) will be true always.
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add_when_exp tests against when_exps, not against when_conds, I don't know if that's what you mean
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Oh, I misread it!! My mistake
#5011 was manually detected, but maybe it's better if the compiler can help us here :-)
Also removes some duplicate cases in the compiler's code and the standard library. You gotta love bootstrapping :-D