These are the functions in the "string" table.
Indices, where used, start at 1 for the first character (not zero). Negative numbers count from the right, so -1 is the last character, -2 the second last, and so on.
All strings have a metatable added to them by Lua with an __index entry pointing to the string table. What this means is that you can write string function calls in two ways:
s = "hello, world"
string.len (s) --> 12
s:len () --> 12
The second version is shorter as the word "string" is implied. Note the colon after the s, not a dot.
See Also ...
Topics
Lua base functions
Lua bc (big number) functions
Lua bit manipulation functions
Lua coroutine functions
Lua debug functions
Lua io functions
Lua math functions
Lua os functions
Lua package functions
Lua PCRE regular expression functions
Lua script extensions
Lua table functions
Lua utilities
Regular Expressions
ScriptingLua functions
string.byte (Converts a character into its ASCII (decimal) equivalent)
string.char (Converts ASCII codes into their equivalent characters)
string.dump (Converts a function into binary)
string.find (Searches a string for a pattern)
string.format (Formats a string)
string.gfind (Iterate over a string (obsolete in Lua 5.1))
string.gmatch (Iterate over a string)
string.gsub (Substitute strings inside another string)
string.len (Return the length of a string)
string.lower (Converts a string to lower-case)
string.match (Searches a string for a pattern)
string.rep (Returns repeated copies of a string)
string.reverse (Reverses the order of characters in a string)
string.sub (Returns a substring of a string)
string.upper (Converts a string to upper-case)(Help topic: general=lua_string)
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