Performs a single composition step of the
Unicode canonical composition algorithm.
This function includes algorithmic Hangul Jamo composition,
but it is not exactly the inverse of g_unichar_decompose().
No composition can have either of a or b equal to zero.
To be precise, this function composes if and only if
there exists a Primary Composite P which is canonically
equivalent to the sequence <a,b>. See the Unicode
Standard for the definition of Primary Composite.
If a and b do not compose a new character, ch is set to zero.
Performs a single composition step of the Unicode canonical composition algorithm.
This function includes algorithmic Hangul Jamo composition, but it is not exactly the inverse of g_unichar_decompose(). No composition can have either of a or b equal to zero. To be precise, this function composes if and only if there exists a Primary Composite P which is canonically equivalent to the sequence <a,b>. See the Unicode Standard for the definition of Primary Composite.
If a and b do not compose a new character, ch is set to zero.
See UAX[15|15]
for details.