.. _stdlib_unicode_text:

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Unicode normalization and canonical caseless comparison
=======================================================

.. das:module:: unicode_text

Module unicode_text



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Constants
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.. _global-unicode_text-UNICODE_TEXT_VERSION:

.. das:attribute:: UNICODE_TEXT_VERSION = "17.0.0"

UNICODE_TEXT_VERSION:string const

.. _global-unicode_text-UNICODE_CASELESS_KEY_VERSION:

.. das:attribute:: UNICODE_CASELESS_KEY_VERSION = "unicode-17.0.0-d145-1"

UNICODE_CASELESS_KEY_VERSION:string const


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Normalization and case folding
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  *  :ref:`try_unicode_casefold (value: string; var result: string&) : bool <function-unicode_text_try_unicode_casefold_string_string_ref_>`
  *  :ref:`try_unicode_caseless_key (value: string; var result: string&) : bool <function-unicode_text_try_unicode_caseless_key_string_string_ref_>`
  *  :ref:`try_unicode_nfd (value: string; var result: string&) : bool <function-unicode_text_try_unicode_nfd_string_string_ref_>`

.. _function-unicode_text_try_unicode_casefold_string_string_ref_:

.. das:function:: try_unicode_casefold(value: string; result: string&) : bool

Full default, locale-independent Unicode case folding. Invalid UTF-8 leaves result unchanged.


:Arguments: * **value** : string

            * **result** : string\ &

.. _function-unicode_text_try_unicode_caseless_key_string_string_ref_:

.. das:function:: try_unicode_caseless_key(value: string; result: string&) : bool

Unicode D145 canonical caseless key: NFD(casefold(NFD(value))). Invalid UTF-8 leaves result unchanged.
Input and output may alias. Preserves accents; does not filter visual confusables or perform locale-specific casing.
Record UNICODE_CASELESS_KEY_VERSION with persisted keys; future changes require explicit reindexing and collision handling.


:Arguments: * **value** : string

            * **result** : string\ &

.. _function-unicode_text_try_unicode_nfd_string_string_ref_:

.. das:function:: try_unicode_nfd(value: string; result: string&) : bool

Canonically decompose valid UTF-8 using Unicode17.0.0. Invalid UTF-8 leaves result unchanged.


:Arguments: * **value** : string

            * **result** : string\ &