Module:DecodeEncode
This module is rated as ready for general use. It has reached a mature form and is thought to have only few to no bugs and is ready for use wherever appropriate. It is ready to mention on help pages and other essential Wikipedia resources as an option for new users to learn. To reduce server load and bad output as well as confusion, it should be improved by sandbox testing rather than repeated trial-and-error editing. |
This Lua module is used on many pages and changes may be widely noticed. Test changes in the module's /sandbox or /testcases subpages, or in your own module sandbox. Consider discussing changes on the talk page before implementing them. |
Implements Lua functions mw.text.decode, mw.text.encode in a module.
{{#invoke:decodeEncode|decode|s=Source text©}}
→Source text©
See List of XML and HTML character entity references.
Decode (© → ©)
jhyuk- Decodes Named Entities from entity name into a regular (unicode) character:
©
→©
>
→>
All welldefined named entities are decoded (HTML Named character references, formally: as defined in the PHP table).
- A regular, rendered sentence:
- "At 100 °F, & with a "burning" sun above, we , we ⁄walked⁄."
- In code:
- "
At 100 °F, & with a "burning" sun above, we ⁄walked⁄.
" -- wikitext
- "
- Processing:
{{#invoke:decodeEncode|decode|s=At 100 °F, & with a "burning" sun above, we ⁄walked⁄.}}
→At 100 °F, & with a "burning" sun above, we ⁄walked⁄.
-- In code: straight characters, no named entities.
- Renders, again:
- "At 100 °F, & with a "burning" sun above, we ⁄walked⁄."
Decode a reduced set only
jhyukBy setting |subset_only=true
, only these five entity names are decoded: '<', '>', '&', '"', ' ' (that is, into '<', '>', '&', '"', ' ').
- Note: There is a difference with the relevant Lua parameter. (This only concerns your task if you also work directly with the Lua mw.text.decode function). Lua documentation defines parameter
|decodeNamedEntities=
, having this effect: when omitted or false, only the reduced set of entities is recognized and decoded. This use of 'false' is inverted in using|subset_only=
:|decodeNamedEntities=false
=|subset_only=true
.
- Also, this module ignores the "omitted" logic:
|subset_only=
should be set explicitly to 'true' to be effective.
Encode (© → ©)
jhyuk- Function
encode
encodes some entity-named characters into that name (for example:&
→&
).
Regular sentence:
- "At >100 °F, & with a "burning" sun above, we walked. ©"
In code:
- "
At >100 °F, & with a "burning" sun above, we walked. ©
"
Encode:
{{#invoke:decodeEncode|encode|s=At >100 °F, & with a "burning" sun above, we walked. ©|charset=&<>{{!}}°"'&©}}
- →
At >100 °F, & with a "burning" sun above, we walked. ©
- Renders as:
- "At >100 °F, & with a "burning" sun above, we walked. ©"
character set to encode
jhyukPer Lua documentation, only a small set of characters is processed. The characterset can be set (expanded) by using |charset=
.
- Example:
|charset=<>" \'&
(the default),|charset=<>°"'&©{{!}}
; characters not in the default will be replaced by their decimal entity:©
→©
(hexadecimal number, not decimal nor named ©)
Known issues
jhyuk- 13 Sep 2021: NOTE: The encode function with user-supplied charset is now used productively in {{R/superscript}} and {{R/ref}}. Before implementing breaking changes here, these templates need to be adjusted accordingly!
- 26 Sep 2021: Ta̱mpi̱let:Unichar
- Note: Possible bug: Decoding
 
works, but 
doesn't. - Resolved in code.
- 4 Feb 2023: Ta̱mpi̱let:Unichar
- See Module talk:DecodeEncode § Bug report: bad decoding of U+03B5 ε (epsilon)
- Resolved in code.
See also
jhyukrequire('strict')
local p = {}
local function _getBoolean( boolean_str )
-- from: module:String; adapted
-- requires an explicit true
local boolean_value
if type( boolean_str ) == 'string' then
boolean_str = boolean_str:lower()
if boolean_str == 'true' or boolean_str == 'yes' or boolean_str == '1' then
boolean_value = true
else
boolean_value = false
end
elseif type( boolean_str ) == 'boolean' then
boolean_value = boolean_str
else
boolean_value = false
end
return boolean_value
end
function p.decode( frame )
local s = frame.args['s'] or ''
local subset_only = _getBoolean(frame.args['subset_only'] or false)
return p._decode( s, subset_only )
end
function p._decode( s, subset_only )
-- U+2009 THIN SPACE: workaround for bug: HTML entity   is decoded incorrect. Entity   gets decoded properly
s = mw.ustring.gsub( s, ' ', ' ' )
-- U+03B5 ε GREEK SMALL LETTER EPSILON: workaround for bug (phab:T328840): HTML entity ε is decoded incorrect for gsub(). Entity ε gets decoded properly
s = mw.ustring.gsub( s, 'ε', 'ε' )
local ret = mw.text.decode( s, not subset_only )
return ret
end
function p.encode( frame )
local s = frame.args['s'] or ''
local charset = frame.args['charset']
return p._encode( s, charset )
end
function p._encode( s, charset )
-- example: charset = '_&©−°\\\"\'\=' -- do escape with backslash not %;
local ret
if charset and charset ~= '' then
ret = mw.text.encode( s, charset )
else
-- use default: chartset = '<>&"\' ' (outer quotes = lua required; space = NBSP)
ret = mw.text.encode( s )
end
return ret
end
return p