ઢાંચો:String templates see also text

Trimming templates:

{{Trunc}} – To trim down to a specified number of characters.
{{Str left}} – To trim down to a specified number of characters, or duplicate the string to a specified number.
{{Str crop}} – To crop a specified number of characters off the end.
{{Chop head and tail}} — To crop a specified number of characters off the beginning and end.
{{Trim}} — To trim any leading or trailing whitespace.
{{First word}} — To trim down to the first space.
{{Remove first word}} — To remove anything before the first space (no accented characters in the string).
{{Remove first word/any}} — To remove anything before the first space (wider range of characters in the string).
{{Str letter/trim}} — To trim down to the beginning letters.
{{Str number/trim}} — To trim down to the beginning numbers.
{{Title without disambig}} — To trim off any parenthesis text at the end of a string.
{{Title disambig text}} – Returns text in parenthesis at the end of a string.
{{Str right}} — To trim the first specified number of characters.
{{Str rightc}} — To trim the first specified number of characters, returns a parameter if the string is empty.
{{Str rightmost}} — To trim down to the last specified number of characters.
{{Str sub}} — To trim down to a specified number, starting at a given number from the left, less than 50.
{{Substr any}} — To trim down to a specified number, starting at a given number from the left, less than 50, can extract accented letters.
{{Str sub long}} — To trim down to a specified number, starting at a given number from the left, less than 100.

Inserting strings:

{{Strloc insert}} - Inserts a string at character location strloc, or appends if strloc<=0.
{{Strloc prefix}} - Extracts string prefix up to location strloc, or whole string if strloc<=0.
{{Str rep}} — Returns the string, replacing the first occurrence of a specified string, with another string. Requires a match.
{{Str repc}} — Returns the string, replacing the first occurrence of a specified string, with another string, if there is one.

Analyzing strings:

{{Str endswith}} – To check if a string ends with a given string.
{{Str find}} – Returns the numerical location of a given string in a string, up to 50 characters.
{{Str find long}} – Returns the numerical location of a given string in a string, up to 80 characters.
{{Strfind short}} – Searches for a short string in a longer (up to 99 char) string. Performs faster than {{str find}}
{{Str find0}} – Very fast zero-based substring search with string support up to 90 characters.
{{Str sub find}} – Searches a substring in a string at the given offset.
{{Str index}} – Returns a given character from a string, but not accented letters.
{{Str index any}} – Returns a given character from a string, but not a space.
{{Chr}} – Returns a given character from a string, including a space.
{{Str len}} – Returns a string's length. Can count up to 500 characters.
{{Strlen quick}} – Gets string length quickly (better performance), up to 70 long.
{{Strlen short}} – Gets length of short strings (1-50), using only 2 expansion levels.
{{Str letter}} — Returns the number of letters that begin a string.
{{Str number}} — Returns the number of numbers that begin a string.
{{Ship prefix}} — Returns the length of a ship name prefix, if listed.

String length comparison templates:

{{Str ≥ len}} – To check if a string is "longer or equally long" or "shorter" than a given length.
{{Str ≤ len}} – To check if a string is "shorter or equally long" or "longer" than a given length.
{{Str ≠ len}} – To check if a string is "not equal" or "equal" to a given length.
{{Str ≤ ≥ len}} – To check if a string is "shorter", "equal", or "longer" than a given length.

Sandboxes and test cases:

Technical stuff:

mw:Help:Magic words – About {{padleft:|}}.
mw:Help:Extension:ParserFunctions – About {{#titleparts:|}}, {{#expr:|}}, {{#ifeq:|}}, etc.

Feature requests:

bugzilla:6455 - Set $wgPFEnableStringFunctions = true on WMF wikis
bugzilla:26092 - Enable or install string parsing wikimarkup functionality on WMF wikis

Future:

status?)