30 lines
694 B
ReStructuredText
30 lines
694 B
ReStructuredText
``defined``
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===========
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``defined`` checks if a variable is defined in the current context. This is very
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useful if you use the ``strict_variables`` option:
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.. code-block:: jinja
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{# defined works with variable names #}
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{% if foo is defined %}
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...
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{% endif %}
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{# and attributes on variables names #}
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{% if foo.bar is defined %}
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...
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{% endif %}
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{% if foo['bar'] is defined %}
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...
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{% endif %}
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When using the ``defined`` test on an expression that uses variables in some
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method calls, be sure that they are all defined first:
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.. code-block:: jinja
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{% if var is defined and foo.method(var) is defined %}
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...
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{% endif %}
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