diff options
author | Georg Brandl <georg@python.org> | 2007-08-15 14:28:22 (GMT) |
---|---|---|
committer | Georg Brandl <georg@python.org> | 2007-08-15 14:28:22 (GMT) |
commit | 116aa62bf54a39697e25f21d6cf6799f7faa1349 (patch) | |
tree | 8db5729518ed4ca88e26f1e26cc8695151ca3eb3 /Doc/library/stringprep.rst | |
parent | 739c01d47b9118d04e5722333f0e6b4d0c8bdd9e (diff) | |
download | cpython-116aa62bf54a39697e25f21d6cf6799f7faa1349.zip cpython-116aa62bf54a39697e25f21d6cf6799f7faa1349.tar.gz cpython-116aa62bf54a39697e25f21d6cf6799f7faa1349.tar.bz2 |
Move the 3k reST doc tree in place.
Diffstat (limited to 'Doc/library/stringprep.rst')
-rw-r--r-- | Doc/library/stringprep.rst | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/Doc/library/stringprep.rst b/Doc/library/stringprep.rst new file mode 100644 index 0000000..b0944e4 --- /dev/null +++ b/Doc/library/stringprep.rst @@ -0,0 +1,142 @@ + +:mod:`stringprep` --- Internet String Preparation +================================================= + +.. module:: stringprep + :synopsis: String preparation, as per RFC 3453 +.. moduleauthor:: Martin v. Löwis <martin@v.loewis.de> +.. sectionauthor:: Martin v. Löwis <martin@v.loewis.de> + + +.. versionadded:: 2.3 + +When identifying things (such as host names) in the internet, it is often +necessary to compare such identifications for "equality". Exactly how this +comparison is executed may depend on the application domain, e.g. whether it +should be case-insensitive or not. It may be also necessary to restrict the +possible identifications, to allow only identifications consisting of +"printable" characters. + +:rfc:`3454` defines a procedure for "preparing" Unicode strings in internet +protocols. Before passing strings onto the wire, they are processed with the +preparation procedure, after which they have a certain normalized form. The RFC +defines a set of tables, which can be combined into profiles. Each profile must +define which tables it uses, and what other optional parts of the ``stringprep`` +procedure are part of the profile. One example of a ``stringprep`` profile is +``nameprep``, which is used for internationalized domain names. + +The module :mod:`stringprep` only exposes the tables from RFC 3454. As these +tables would be very large to represent them as dictionaries or lists, the +module uses the Unicode character database internally. The module source code +itself was generated using the ``mkstringprep.py`` utility. + +As a result, these tables are exposed as functions, not as data structures. +There are two kinds of tables in the RFC: sets and mappings. For a set, +:mod:`stringprep` provides the "characteristic function", i.e. a function that +returns true if the parameter is part of the set. For mappings, it provides the +mapping function: given the key, it returns the associated value. Below is a +list of all functions available in the module. + + +.. function:: in_table_a1(code) + + Determine whether *code* is in tableA.1 (Unassigned code points in Unicode 3.2). + + +.. function:: in_table_b1(code) + + Determine whether *code* is in tableB.1 (Commonly mapped to nothing). + + +.. function:: map_table_b2(code) + + Return the mapped value for *code* according to tableB.2 (Mapping for + case-folding used with NFKC). + + +.. function:: map_table_b3(code) + + Return the mapped value for *code* according to tableB.3 (Mapping for + case-folding used with no normalization). + + +.. function:: in_table_c11(code) + + Determine whether *code* is in tableC.1.1 (ASCII space characters). + + +.. function:: in_table_c12(code) + + Determine whether *code* is in tableC.1.2 (Non-ASCII space characters). + + +.. function:: in_table_c11_c12(code) + + Determine whether *code* is in tableC.1 (Space characters, union of C.1.1 and + C.1.2). + + +.. function:: in_table_c21(code) + + Determine whether *code* is in tableC.2.1 (ASCII control characters). + + +.. function:: in_table_c22(code) + + Determine whether *code* is in tableC.2.2 (Non-ASCII control characters). + + +.. function:: in_table_c21_c22(code) + + Determine whether *code* is in tableC.2 (Control characters, union of C.2.1 and + C.2.2). + + +.. function:: in_table_c3(code) + + Determine whether *code* is in tableC.3 (Private use). + + +.. function:: in_table_c4(code) + + Determine whether *code* is in tableC.4 (Non-character code points). + + +.. function:: in_table_c5(code) + + Determine whether *code* is in tableC.5 (Surrogate codes). + + +.. function:: in_table_c6(code) + + Determine whether *code* is in tableC.6 (Inappropriate for plain text). + + +.. function:: in_table_c7(code) + + Determine whether *code* is in tableC.7 (Inappropriate for canonical + representation). + + +.. function:: in_table_c8(code) + + Determine whether *code* is in tableC.8 (Change display properties or are + deprecated). + + +.. function:: in_table_c9(code) + + Determine whether *code* is in tableC.9 (Tagging characters). + + +.. function:: in_table_d1(code) + + Determine whether *code* is in tableD.1 (Characters with bidirectional property + "R" or "AL"). + + +.. function:: in_table_d2(code) + + Determine whether *code* is in tableD.2 (Characters with bidirectional property + "L"). + |