diff --git a/IPython/html/widgets/widget_selection.py b/IPython/html/widgets/widget_selection.py
index 5193fb183..228498b1c 100644
--- a/IPython/html/widgets/widget_selection.py
+++ b/IPython/html/widgets/widget_selection.py
@@ -55,6 +55,7 @@ class _Selection(DOMWidget):
def __init__(self, *args, **kwargs):
self.value_lock = Lock()
self.options_lock = Lock()
+ self.equals = kwargs.pop('equals', lambda x, y: x == y)
self.on_trait_change(self._options_readonly_changed, ['_options_dict', '_options_labels', '_options_values', '_options'])
if 'options' in kwargs:
self.options = kwargs.pop('options')
@@ -105,13 +106,14 @@ class _Selection(DOMWidget):
def _options_readonly_changed(self, name, old, new):
if not self.options_lock.locked():
raise TraitError("`.%s` is a read-only trait. Use the `.options` tuple instead." % name)
+
def _value_changed(self, name, old, new):
"""Called when value has been changed"""
if self.value_lock.acquire(False):
try:
# Reverse dictionary lookup for the value name
for k, v in self._options_dict.items():
- if new == v:
+ if self.equals(new, v):
# set the selected value name
self.selected_label = k
return