pango:attr-list-update (attrlist pos remove add)

attrlist -- a pango:attr-list instance
pos -- an integer for the position of the change
remove -- an integer for the number of removed bytes
add -- an integer for the number of added bytes

Update indices of attributes in the attribute list for a change in the text they refer to. The change that this function applies is removing remove bytes at position pos and inserting add bytes instead.

Attributes that fall entirely in the (pos, pos + remove) range are removed. Attributes that start or end inside the (pos, pos + remove) range are shortened to reflect the removal. Attributes start and end positions are updated if they are behind pos + remove.

Since 1.44