[DSSv3] Issue 21637: trailing comma in import list

[dorianverna17]

Added an example of the functionality implemented in the pull request dlang/dmd#12917 at the section regarding selective imports

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✗	21637	enhancement	Allow trailing comma in the ImportList

[dkorpel]

I don't think this is worth bringing attention to in the specification. Trailing commas are allowed in general (argument list, array literal, enum members, case statement) and there are no examples there either.

[dorianverna17]

Should I close this pull request @dkorpel ?

[dkorpel]

Should I close this pull request @dkorpel ?

The change should still be reflected in the grammar:

dlang.org/spec/module.dd

Lines 196 to 199 in 0a90480

	$(GNAME ImportList):
	$(GLINK Import)
	$(GLINK ImportBindings)
	$(GLINK Import) $(D ,) $(GSELF ImportList)

You can use this PR to do that. For reference, here's how ParameterList is specified:

dlang.org/spec/function.dd

Lines 33 to 37 in 0a90480

	$(GNAME ParameterList):
	$(GLINK Parameter)
	$(GLINK Parameter) $(D ,)
	$(GLINK Parameter) $(D ,) $(GSELF ParameterList)
	$(GLINK VariadicArgumentsAttributes)$(OPT) $(D ...)

[dkorpel]

From the implementation it seems you actually modified ImportBindList, not ImportList, so I pointed you to the wrong rule. Also, your implementation allows an empty bind list, but the grammar does not unless you add $(OPT) behind ImportBindList (similar to ParameterList as well).