GSFont replaceObjectInFeaturesAtIndex:withObject:

func replaceFeature(at idx: UInt, with feature: GSFeature)

- (void) replaceObjectInFeaturesAtIndex:(NSUInteger) idx withObject:(GSFeature *) feature;

replaceObjectInFeaturesAtIndex_withObject_(idx: int, feature: GSFeature)

features
Layout features used when compiling OpenType feature code.
countOfFeaturescountOfFeatures
Number of layout features.
objectInFeaturesAtIndex:objectInFeaturesAtIndex_
Layout feature at an index, or nil when the index is out of range.
indexOfFeature:indexOfFeature_
Index of a layout feature, or NSNotFound when the feature is not in the font.
featureForTag:featureForTag_
Returns the first layout feature with a tag.
activeFeatureForTag:activeFeatureForTag_
Returns the first enabled layout feature with a tag.
automaticFeatureForTag:automaticFeatureForTag_
Returns the first automatic layout feature with a tag.
automaticFeatureForTag:hasAnyFeature:automaticFeatureForTag_hasAnyFeature_
Returns the first automatic layout feature with a tag.
addFeature:addFeature_
Adds a layout feature.
insertObject:inFeaturesAtIndex:insertObject_inFeaturesAtIndex_
Inserts a layout feature at an index.
removeFeature:removeFeature_
Removes a layout feature.
removeObjectFromFeaturesAtIndex:removeObjectFromFeaturesAtIndex_
Removes the layout feature at an index.
updateFeatures:updateFeatures_
Updates automatic layout features and classes.
importFeatures:error:importFeatures_error_
Imports OpenType feature code into the font.

replaceFeature(at:with:)replaceObjectInFeaturesAtIndex:withObject:replaceObjectInFeaturesAtIndex_withObject_