Discard calc operations that operate on zero values

[ben-eb]

Would it be possible to discard parts of the calc() function that operate on zero values? For example:

div {
    width: calc(100vw / 2 - 6px + 0px);
}

Can be:

div {
    width: calc(100vw / 2 - 6px);
}

And:

div {
    width: calc(500px - 0px);
}

Can be:

div {
    width: 500px;
}

It's from this edge case in CSSO:

css/csso#222

[MoOx]

calc(500px - 0px) is already transformed to 500px.

You can try here http://cssnext.github.io/cssnext-playground/ since cssnext use postcss-calc which use this package ;)

For the first example, we need to handle math operator priorities (which is not the case for now).
I am open for a PR for this.

Meanwhile, maybe you can do something like:

div {
    width: calc(100vw / 2 - (6px + 0px));
}

which is transformed to

div {
    width: calc(100vw / 2 - 6px);
}

[ben-eb]

Didn't realise that was already transformed, thanks 👍

Perhaps it's possible to use this module for it? https://www.npmjs.com/package/math-analysis - though I've got a lot on my plate at the minute so I probably won't be able to work on a PR right away.

[ben-eb]

Resolved in https://github.com/MoOx/reduce-css-calc/releases/tag/v2.0.0.