premake/util/sdl_string.lua
changeset 7925 f090a47eb7f7
child 8149 681eb46b8ac4
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/premake/util/sdl_string.lua	Sun Nov 10 00:38:37 2013 -0500
@@ -0,0 +1,103 @@
+-- Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>
+--
+-- This software is provided 'as-is', without any express or implied
+-- warranty.  In no event will the authors be held liable for any damages
+-- arising from the use of this software.
+--
+-- Permission is granted to anyone to use this software for any purpose,
+-- including commercial applications, and to alter it and redistribute it
+-- freely.
+--
+-- Meta-build system using premake created and maintained by
+-- Benjamin Henning <b.henning@digipen.edu>
+
+--[[
+sdl_string.lua
+
+	Contains a few convenient string utility functions which are not supported in
+	Lua or not supported as intended.
+]]
+
+-- Performs a non-pattern based substring search of one string in another
+-- string. It's of O(n^2) complexity. It returns nil if the result cannot be
+-- found, otherwise it returns the starting index of the first found occurrence.
+string.indexOf = function(str, substr)
+	local pos = 1
+	local i = 1
+	for i = 1, str:len(), 1 do
+		if str:sub(i, i) == substr:sub(pos, pos) then
+			-- have we matched the complete string?
+			if pos == substr:len() then
+				return i - pos + 1-- starting pos
+			end
+			-- matched character...keep going
+			pos = pos + 1
+		else
+			-- restart, no match
+			pos = 0
+		end
+	end
+	if pos == substr:len() then
+		return i - pos + 1
+	end
+	return nil -- no match
+end
+
+-- This is a public-access version of the explode function defined below.
+function explode(str, delim)
+	return str:explode(delim)
+end
+
+-- Explodes a string into an array of elements, separated by a non-pattern
+-- delimiter. This function is part of the string table, allowing for a
+-- member-based invocation for strings.
+string.explode = function(str, delim)
+	local exploded = { }
+	local needle = string.find(str, delim)
+	while needle ~= nil do
+		table.insert(exploded, string.sub(str, 0, needle - 1))
+		str = string.sub(str, needle + 1)
+		needle = string.find(str, delim)
+	end
+	table.insert(exploded, str)
+	return exploded
+end
+
+-- Similar to table.concat, except it supports more advanced token pasting. This
+-- function is vastly used by the main meta-build script (premake4.lua) to
+-- generate all the main lines of code for various tables that need to be in the
+-- generated lua file.
+--  - tbl: table of values to implode into a string
+--  - prefix: string to paste before entire result
+--  - pre: string to always paste before each entry in table
+--  - post: string to always paste after each entry in table
+--  - join: string to paste between entries (inclusive)
+--  - suffix: string to paste after entire result
+-- Returns the imploded string.
+function implode(tbl, prefix, pre, post, join, suffix)
+	local result = ""
+	-- not the most efficient way to do this, but...
+	local itbl = { }
+	for k,v in pairs(tbl) do
+		itbl[#itbl + 1] = v
+	end
+	for i = 1, #itbl, 1 do
+		if pre ~= nil then
+			result = result .. pre
+		end
+		result = result .. itbl[i]
+		if post ~= nil then
+			result = result .. post
+		end
+		if i ~= #itbl then
+			result = result .. join
+		end
+	end
+	if prefix ~= nil then
+		result = prefix .. result
+	end
+	if suffix ~= nil then
+		result = result .. suffix
+	end
+	return result
+end
\ No newline at end of file