Source code for bokeh.core.property.struct

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# Copyright (c) 2012 - 2018, Anaconda, Inc. All rights reserved.
#
# Powered by the Bokeh Development Team.
#
# The full license is in the file LICENSE.txt, distributed with this software.
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''' Provide the Struct property.

'''

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# Boilerplate
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from __future__ import absolute_import, division, print_function, unicode_literals

import logging
log = logging.getLogger(__name__)

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# Imports
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# External imports
from six import iteritems

# Bokeh imports
from .bases import ParameterizedProperty

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# Globals and constants
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__all__ = (
    'Struct',
)

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# General API
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class Struct(ParameterizedProperty):
    ''' Accept values that are structures.


    '''
    def __init__(self, **fields):
        default = fields.pop("default", None)
        help = fields.pop("help", None)

        self._fields = {}
        for name, type in fields.items():
            self._fields[name] = self._validate_type_param(type)

        super(Struct, self).__init__(default=default, help=help)

    @property
    def type_params(self):
        return list(self._fields.values())

    def validate(self, value, detail=True):
        super(Struct, self).validate(value, detail)

        if value is None:
            return

        if isinstance(value, dict) and len(value) <= len(self._fields):
            for name, type in iteritems(self._fields):
                if not type.is_valid(value.get(name, None)):
                    break
            else:
                return

        msg = "" if not detail else "expected an element of %s, got %r" % (self, value)
        raise ValueError(msg)

    def __str__(self):
        fields = [ "%s=%s" % (name, type) for name, type in self._fields.items() ]
        return "%s(%s)" % (self.__class__.__name__, ", ".join(fields))

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# Dev API
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# Private API
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# Code
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