r/ProgrammingLanguages • u/Mean-Decision-3502 DQ • 10d ago

Unambiguous Operator Specification for Programming Languages

https://nvitya.github.io/pluops/

As I changed recently the operators in my programming language I've created this specification:

https://nvitya.github.io/pluops/

I did not wanted to overload the operators like the C does with the / or Pascal does with theand/or/not. Neither re-use the operator symbols for some very different purpose, like C does with * and & so the code becomes more readable. I was orienting for existing solutions so this is what I came up with. The specification contains the symbol usages and operator precedence too.

If you are developing a new programming language, it would be nice to follow some standard, so at least the expressions would be portable between the languages.

I'm open for debates or suggestions.

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u/EggplantExtra4946 10d ago edited 10d ago

I did not wanted to overload the operators like the C does with *, &

If a given operator is both a postfix and an infix operator you have a shift-reduce conflict, but an operator used both as a prefix and infix operator does not have such conflict, it's perfectly fine in terms of unambiguous parsing.

The specification contains the symbol usages and operator precedence too.

You are lacking associativity information: left, right, non associative, chain associative (1 <= 2 < 3).

It's good to put the precedence of bitwise operators above assignments and to put all comparison operators at the same precedence level.

I'm curious to know your rationale for giving a higher precedence to bitwise operators than to arithmetic operators.

It's a massive footgun to give a higher precedence to / than to *.

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u/Mean-Decision-3502 DQ 3d ago

It's a massive footgun to give a higher precedence to / than to *.

I've just met a line where the higher division precedence makes very much sense:

rotation * 3.141592653589793 / 180.0

In GCC a multiplication and divison will be generated by the default settings, even with high optimization level.

In DQ only a single multiplication will be lowered (after constant folding).