---
title: kUnicodeMatchUnicodeBaseMask
framework: Core Services
role: symbol
role_heading: Enumeration Case
platforms: [Mac Catalyst 17.0+, macOS 10.0+]
path: coreservices/1433554-unicode_matching_masks/kunicodematchunicodebasemask
---

# kUnicodeMatchUnicodeBaseMask

If set, excludes mappings that do not match the text encoding base of the unicodeEncoding field of the structure UnicodeMapping. If not set, the function ignores the text encoding base of that field.

## Declaration

```occ
kUnicodeMatchUnicodeBaseMask = 1L << kUnicodeMatchUnicodeBaseBit
```