section deals with predicates for language-specific string comparison
- Create a Key from Atom for locale-specific
comparison. The key is defined such that if the key of atom A
precedes the key of atom B in the standard order of terms, A
is alphabetically smaller than B using the sort order of the
The predicate collation_key/2
is used by locale_sort/2
from library(sort). Please examine the implementation of locale_sort/2
as an example of using this call.
The Key is an implementation-defined and generally
unreadable string. On systems that do not support locale handling, Key
is simply unified with Atom.
- Sort a list of atoms using the current locale. List is a list
of atoms or string objects (see section
5.2). Sorted is unified with a list containing all atoms
of List, sorted to the rules of the current locale. See also collation_key/2