o ^i|@sdZddlmZmZmZddlmZddlmZm Z m Z m Z Gddde Z eGdd d eZ d d ZeGd d d e ZddZdS)z]Link and DirectionalLink classes. Propagate changes between widgets on the javascript side. )Widgetregisterwidget_serialization) CoreWidget)UnicodeTupleInstance TraitErrorcs0eZdZdZdZfddZfddZZS)WidgetTraitTuplez>> c = link((widget1, 'value'), (widget2, 'value')) )r*)attr1attr2rrrjslinkA r7c@s eZdZdZedjddZdS)DirectionalLinkzA directional link source: a (Widget, 'trait_name') tuple for the source trait target: a (Widget, 'trait_name') tuple that should be updated when the source trait changes. DirectionalLinkModelTr,N)rr%r&r'rr2r3rrrrr9Tsr9cCr4)aLink a source widget attribute with a target widget attribute. The link is created in the front-end and does not rely on a roundtrip to the backend. Parameters ---------- source : a (Widget, 'trait_name') tuple for the source trait target : a (Widget, 'trait_name') tuple for the target trait Examples -------- >>> c = dlink((src_widget, 'value'), (tgt_widget, 'value')) )r9)r.r/rrrjsdlink_r8r;N)r'r!rrr widget_corer traitletsrrr r r r*r7r9r;rrrrs