Nanfeng

Notes on software development, code, and curious ideas

Split Strings in Cocos2d-x Lua with Single or Multi-Character Delimiters

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Implement a Cocos2d-x Lua string-split helper with string.find and string.sub that treats single or multi-character delimiters literally and returns an array.

This helper splits a string using a literal delimiter and returns the pieces in an array:

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function string.split(input, delimiter)
    input = tostring(input)
    delimiter = tostring(delimiter)

    if delimiter == '' then
        return false
    end

    local position = 1
    local result = {}

    while true do
        local startPos, endPos = string.find(
            input,
            delimiter,
            position,
            true
        )

        if not startPos then
            table.insert(result, string.sub(input, position))
            break
        end

        table.insert(result, string.sub(input, position, startPos - 1))
        position = endPos + 1
    end

    return result
end

Examples:

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string.split("Hello,World", ",")
-- {"Hello", "World"}

string.split("Hello-+-World-+-Quick", "-+-")
-- {"Hello", "World", "Quick"}

The fourth argument to string.find is true, so the delimiter is treated as plain text rather than a Lua pattern.

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