Coding style

General

• Indentation - 4 spaces
• Line Length - 80 characters

Naming

• Classnames - UpperCamelCase
• Functions - lowerCamelCase
• Variables - all_lower_case_with_underscores
• Constants - ALL_UPPER_CASE_WITH_UNDERSCORES
• Filenames - shortnouns

exceptions:

• global variables should be prefixed with G_: G_width
• boolean variables should be prefixed as predicates: is_directory
• i, k, v, and t are often used as follows:

for k,v in pairs(t) ... end
for i,v in ipairs(t) ... end
mt.__newindex = function(t, k, v) ... end

Order of Requires

Please order the requires in following rules, local Class = require("class") -- Uppercase class local Device = require("device") -- Uppercase class local func = require("func") -- Lowercase function local glob = require("glob") -- Lowercase function local _ = require("gettext") -- Symbol local T = require("ffi/util").template -- One of the functions in a file local V = require("utils2").version -- The other function, ordered by ASCII.

Tips

• Use locals rather than globals whenever possible.

• End terminator

Because "end" is a terminator for many different constructs, it can help the reader (especially in a large block) if a comment is used to clarify which construct is being terminated:

for i,v in ipairs(t) do
    if type(v) == "string" then
        ...lots of code here...
    end -- if string
end -- for each t

• Check empty table

Determine if a table t is empty (including non-integer keys, which #t ignores):

    if next(t) == nil then ...

Reference: http://lua-users.org/wiki/LuaStyleGuide