Feature request: Option to remove declarations

[bartelsmedia]

Hello from a Less noobie,

We patch/alter the original bootstrap.less with a custom.less file

Many declarations made in the main bootstrap.less file are not required for our projects and we would like to keep the source files untouched so we can just drop in any update in the same folder without any modification.

Is there a way to tell in custom.less to remove/ignore declarations made in bootstrap.less from the compiled output?

Example:

Following declaration is defined in bootstrap.less:

@gray-darker: lighten(#000, 13.5%);

While we don't need this declaration, it will be rendered into the output.css (unless we would modify the original source bootstrap.less).

It would be nice, if a prefix, added in the custom.less, could make this declaration be removed from the output, e.g. with a leading minus char:

-@gray-darker

This would minimize the compiled .css without touching the original files. I hope this does make any sense.

[seven-phases-max]

While we don't need this declaration, it will be rendered into the output.css

No, it won't. Variables are part of Less and they are not rendered into the compiled CSS (it would result in an invalid CSS if they are).

[bartelsmedia]

Well, OK, it was a poor example. For the rescue, take any generated css that is generated by the bootstrap.less

Another example:

.nav-stacked {

li {
float: none;
+ li {margin-top: 2px;}
}
}

If 'prefixed' by a minus in a linked .less, the whole rule declaration set wouldn't be rendered:

-.nav-stacked {

li {
float: none;
+ li {margin-top: 2px;}
}
}

[seven-phases-max]

See #1372.

[seven-phases-max]

Closing as duplicate of #1372.