在string.gmatch中的Lua string.gsub?

时间:2015-01-15 04:06:30

标签: lua gsub lua-patterns

我创建了这个简单的示例脚本来输出食物列表。如果食物是水果,那么水果的颜色也会显示出来。我遇到的问题是处理草莓的不规则多元化问题。'

fruits = {apple = "green", orange = "orange", stawberry = "red"}
foods = {"potatoes", "apples", "strawberries", "carrots", "crab-apples"}

for _, food in ipairs(foods) do
    for fruit, fruit_colour in pairs(fruits) do
        duplicate = false
        if (string.match(food, "^"..fruit) or string.match((string.gsub(food, "ies", "y")), "^"..fruit)) and not(duplicate) then -- this is where the troubles is!
            print(food.." = "..fruit_colour)
            duplicate = true
            break
        end
    end
    if not(duplicate) then
        print(food)
    end
end

现在程序输出:

potatoes
apples = green
strawberries
carrots
crab-apples

我想要的是:

potatoes
apples = green
strawberries = red
carrots
crab-apples

我无法弄清楚为什么这样做并不像我想要的那样!

2 个答案:

答案 0 :(得分:4)

好吧,有一件事,你在这里拼错了草莓:

fruits = {apple = "green", orange = "orange", stawberry = "red"}

您也可以将lua表作为集合使用,这意味着不需要嵌套循环搜索重复项。它可以简化为:

fruits = {apple = "green", orange = "orange", strawberry = "red"}
foods = {"potatoes", "apples", "strawberries", "carrots", "crab-apples"}

function singular(word)
    return word:gsub("(%a+)ies$", "%1y"):gsub("(%a+)s$", "%1")
end

for _, food in ipairs(foods) do
    local single_fruit = singular(food)
    if fruits[single_fruit] then
        print(food .. " = " .. fruits[single_fruit])
    else
        print(food)
    end
end

答案 1 :(得分:2)

stawberry应为strawberry。循环将strawberries更改为strawberry,然后尝试将strawberry^stawberry匹配,但错字导致它不匹配。