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by Calavar 544 days ago
In languages (both natural and machine languages) a certain amount of syntax redundancy is a feature. The point of syntax "boilerplate" is to turn typos into syntax errors. When you have a language without any redundant syntactical features, you run the risk that your typo is also valid syntax, just with different semantics than what you intended. IMHO, that's much worse than dealing with a missing semicolon error.
1 comments
mckn1ght 544 days ago
Can you provide an example where syntax that’s required to be typed and can be accurately diagnosed by the compiler can lead to unintended logic? This is not the same thing as like not typing curly braces under an if directive and then adding a second line under it.
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Calavar 543 days ago
> Can you provide an example where syntax that’s required to be typed and can be accurately diagnosed by the compiler can lead to unintended logic?

I'm not sure we are on the same page here. I'm saying the absence of redundant syntax of the sort that lets the compiler accurately diagnose 'trivial' syntax errors, that can create scenarios where a typo can give you unintended valid syntax with different logic.

So yes, the conditional shorthand in C would be an example. Getting rid of the braces means you lose an opportunity for the compiler to catch a 'trivial' syntax error, which can lead to different semantics than what the writer intended.

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mckn1ght 543 days ago
Yes, these are different things, which is why I discounted curly braces before. Those are not required for an if statement’s scope. Semicolon’s are “required” everywhere. The compiler can easily spot where one should be by parsing an invalid expression because it encounters illegal tokens to append onto the end of a valid expression, eg you cannot have one statement that contains two assignment operators at the same level of precedence.

However for curly brances around a conditional lexical scope, the compiler cannot tell you where the closing brace should be, besides before the end of the lexical scope that contains it, like the end of the containing function or class. There can be multiple valid locations before that: every other valid line of code. This is not the same as a semicolon, which must end every line of code.

Can you provide another example?

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