To address the new redux-saga action creator support

[ssynix]

Adding the toString field for better redux-saga support.

redux-saga docs mention this under take pattern:

Note: if the pattern function has toString defined on it, action.type will be tested against pattern.toString() instead. This is useful if you're using an action creator library like redux-act or redux-actions.

[aikoven]

Thanks! I'll make a release shortly.

[aikoven]

Released v2.4.0