lua_stringbuffer

Lua library for the supposedly-efficient concatenation of strings.

According to PiL, repeated calls to Lua's built-in .. operator is rather slow. To avoid this, the lua_stringbuffer library uses a table to build up a string and then concatenate them when desired.

To use, just put lua_stringbuffer somewhere in your package path and require it.

local lua_stringbuffer = require 'lua_stringbuffer'
local buffer = lua_stringbuffer.new()
assert(buffer:getString() == '')
buffer:add('my first add')
buffer:add('ition')
assert(buffer:getString() == 'my first addition')

-- non-OOP syntax is supported:
buffer = lua_stringbuffer.new()
lua_stringbuffer.add(buffer, 'my first addition')
assert(lua_stringbuffer.getString(buffer) == 'my first addition')

API Reference

lua_stringbuffer.new([suffix])

Returns a new 'StringBuffer' table/object. suffix is an optional string that will be added after each call to add() and defaults to the empty string. Raises an error iff

type(suffix) ~= 'string' or type(suffix) ~= 'nil'`

The following calls are equivalent:

bufferobj = lua_stringbuffer.new(suffix)

bufferobj = lua_stringbuffer.new()
bufferobj:setSuffix(suffix)

lua_stringbuffer.setSuffix(bufferobj[, suffix])

Sets a string to be appended at the end of each add() call. If nil, sets the empty string. Raises an error iff

type(suffix) ~= 'string' or type(suffix) ~= 'nil'`

lua_stringbuffer.add(bufferobj[, ...])

Add one or more strings to the end of the buffer. Accepts a any number of arguments of any type, with behavior as follows:

• iterates over the arguments in-order adding until the first non-string element, at which point it will halt, add the bufferobj's set separator (if any) and return.
• if and only if the first agument is a table, it follows the same rules as above with the table's indices 1..n. The table may have a key suffix which holds a string which will be inserted after each added element from the table; when the first non-string element is encountered, the bufferobj's set separator will be added and the function will return.

buffer = lua_stringbuffer.new('\n')
buffer:add({suffix = '\t', 'apples', 'tangerines', 'kiwis', true, 'bananas'})
buffer:getString() == 'apples\ttangerines\tkiwis\t\n'

lua_stringbuffer.getString(bufferobj)

Returns the string literal that is the concatenation of all additions (and appropriate separators).

Examples

coming soon