aptana/studio3 — comment on commit 5d79dad8ac665b8dd584abb9e8eb537eef7a21c3
File: plugins/com.aptana.editor.common/src/com/aptana/editor/common/validator/LegacyValidationBuildParticipant.java line 66
By thelonious:

You could use a Set for the selectedValidators and then test for existence (contains) for each validator. That will avoid the O(M*N) case from the cross-product here.