pseudo-lang / pseudo

transpile algorithms/libs to idiomatic JS, Go, C#, Ruby
MIT License
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Parenthesise operators if necessary #16

Open atg opened 8 years ago

atg commented 8 years ago

In Python the not operator has low precedence. In JS the ! operator has high precedence.

To be on the safe side, generators should wrap all operators in parens by default, and only remove them if the generator can prove there is no precedence/associativity issue. Otherwise you'll get issues with things like PHP's weird-ass left associative ternary operator.

Input (Python):

not 0.1 > 0.1

Expected output (JavaScript):

!(0.1 > 0.1)

Actual output (JavaScript):

!0.1 > 0.1

alehander92 commented 8 years ago

There is already a dict with operator precedence order in the base code generator. It was in one of the initial python generator versions and it was good enough for the alpha release, but now I can just overload some of the precedences in the language specific generators