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Features:
- Added support for implicit translation:
The ``implicit_i18n_translate`` option enables implicit translation
of text. The ``implicit_i18n_attributes`` enables implicit
translation of attributes. The latter must be a set and for an
attribute to be implicitly translated, its lowercase string value
must be included in the set.
- Added option ``strict`` (enabled by default) which decides whether
expressions are required to be valid at compile time. That is, if
not set, an exception is only raised for an invalid expression at
evaluation time.
- An expression error now results in an exception only if the
expression is attempted evaluated during a rendering.
- Added a configuration option ``prepend_relative_search_path`` which
decides whether the path relative to a file-based template is
prepended to the load search path. The default is ``True``.
- Added a configuration option ``search_path`` to the file-based
template class, which adds additional paths to the template load
instance bound to the ``load:`` expression. The option takes a
string path or an iterable yielding string paths. The default value
is the empty set.
Bugfixes:
- Exception instances now support pickle/unpickle.
- An attributes in i18n:attributes no longer needs to match an
existing or dynamic attribute in order to appear in the
element. This fixes issue 66.