2 FFLuCI - Utility library
5 Several common useful Lua functions
11 Copyright 2008 Steven Barth <steven@midlink.org>
13 Licensed under the Apache License, Version 2.0 (the "License");
14 you may not use this file except in compliance with the License.
15 You may obtain a copy of the License at
17 http://www.apache.org/licenses/LICENSE-2.0
19 Unless required by applicable law or agreed to in writing, software
20 distributed under the License is distributed on an "AS IS" BASIS,
21 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 See the License for the specific language governing permissions and
23 limitations under the License.
27 module("ffluci.util", package.seeall)
30 -- Lua simplified Python-style OO class support emulation
34 local create = function(class, ...)
36 setmetatable(inst, {__index = class})
39 local stat, err = pcall(inst.__init__, inst, ...)
48 local classmeta = {__call = create}
51 classmeta.__index = base
54 setmetatable(class, classmeta)
59 -- Clones an object (deep on-demand)
60 function clone(object, deep)
63 for k, v in pairs(object) do
64 if deep and type(v) == "table" then
70 setmetatable(copy, getmetatable(object))
76 -- Checks whether a table has an object "value" in it
77 function contains(table, value)
78 for k,v in pairs(table) do
87 -- Dumps a table to stdout (useful for testing and debugging)
88 function dumptable(t, i)
90 for k,v in pairs(t) do
91 print(string.rep("\t", i) .. k, v)
92 if type(v) == "table" then
99 -- Escapes all occurences of c in s
100 function escape(s, c)
102 return s:gsub(c, "\\" .. c)
106 -- Populate obj in the scope of f as key
107 function extfenv(f, key, obj)
108 local scope = getfenv(f)
113 -- Checks whether an object is an instanceof class
114 function instanceof(object, class)
115 local meta = getmetatable(object)
116 while meta and meta.__index do
117 if meta.__index == class then
120 meta = getmetatable(meta.__index)
126 -- Creates valid XML PCDATA from a string
127 function pcdata(value)
128 value = value:gsub("&", "&")
129 value = value:gsub('"', """)
130 value = value:gsub("'", "'")
131 value = value:gsub("<", "<")
132 return value:gsub(">", ">")
136 -- Resets the scope of f doing a shallow copy of its scope into a new table
138 setfenv(f, clone(getfenv(f)))
142 -- Splits a string into an array
143 function split(str, pat, max, regex)
163 local s, e = str:find(pat, c, not regex)
164 table.insert(t, str:sub(c, s and s - 1))
166 c = e and e + 1 or #str + 1
167 until not s or max < 0
172 -- Removes whitespace from beginning and end of a string
173 function trim(string)
174 local s = string:gsub("^%s*(.-)%s*$", "%1")
178 -- Updates given table with new values
179 function update(t, updates)
180 for k, v in pairs(updates) do
186 -- Updates the scope of f with "extscope"
187 function updfenv(f, extscope)
188 update(getfenv(f), extscope)
192 -- Validates a variable
193 function validate(value, cast_number, cast_int)
194 if cast_number or cast_int then
195 value = tonumber(value)
198 if cast_int and value and not(value % 1 == 0) then