Problems mixing-in rulesets defined using & combinator

[tcjr]

When I use the & combinator to define a ruleset like this:

.label {
  &-success {
    background-color: blue;
   }
}

This correctly creates css like this:

.label-success {
  background-color: blue;
}

However, when I try to add/mixin the label-success ruleset into another, like this:

.mySuccessLabel {
  .label-success;
}

It fails compilation with: "Name error: .label-success is undefined"

Here is the complete example showing the error:

.label {
  &-success {
    background-color: blue;
   }
}

.mySuccessLabel {
  .label-success;
}

I am using twitter bootstrap. They define labels and badges like above. https://github.com/twitter/bootstrap/blob/master/less/labels-badges.less#L52

[lukeapage]

we had this bug before but I can't find it.

The answer was to use extends. These are in 1.4.0 beta.

It is unfortunately a limittation of the way mixins work that it would be difficult to compare to parts, e.g. &-success is evaluated after mixins are calculated.

[tcjr]

I believe I found the issue you are talking about. Is it #1248 ?

In any event, I don't think the extend functionality, as currently implement, fixes this problem. Suppose we update the sample above to use extend, like so:

.label {
  &-success {
    background-color: blue;
   }
}
.mySuccessLabel:extend(.label-success) { }

This produces no rules for .mySuccessLabel.

Isn't this a bug? If not, then is there any workaround besides not using the & combinator in the original file?

[lukeapage]

hrmm, your right.. I know why.. its because it treats it as

combinator .
element label
combinator blank
element -success

[ArturKwiatkowski]

I've run into that problem just recently while delivering more nested rules for bootstrap 3.0.0-wip (labels component), removed the short name combination in the end and im awaiting for merge. Removed because that &-name combination didnt work and i really want to use bootstrap classes as mixins in my Less mastersheet instead writing ton of classes in my html markup. Other thing im interested is a ability to make loops - can anyone point me anywhere if thats something that is/will be supported?

[lukeapage]

@Fowowski #1267 (comment)

[lukeapage]

duplicate of #1196