Stylus中文
循环迭代(Iteration)
Stylus允许你通过for/in对表达式进行迭代，形式如下：
for <val-name> [, <key-name>] in <expression>
for <val-name> [, <key-name>] in <expression>
For example:
body
for num in 1 2 3
foo num
body
for num in 1 2 3
foo num
编译为:
body {
foo: 1;
foo: 2;
foo: 3;
}
body {
foo: 1;
foo: 2;
foo: 3;
}
下面这个例子演示了如何使用 <key-name>:
body
fonts = Impact Arial sans-serif
for font, i in fonts
foo i font
body
fonts = Impact Arial sans-serif
for font, i in fonts
foo i font
编译为:
body {
foo: 0 Impact;
foo: 1 Arial;
foo: 2 sans-serif;
}
body {
foo: 0 Impact;
foo: 1 Arial;
foo: 2 sans-serif;
}
And here's how you do a regular for loop
body
for num in (1..5)
foo num
body
for num in (1..5)
foo num
Yields:
body {
foo: 1;
foo: 2;
foo: 3;
foo: 4;
foo: 5;
}
body {
foo: 1;
foo: 2;
foo: 3;
foo: 4;
foo: 5;
}
使用字符串:
for num in (1..10)
.box{num}
animation: box + num 5s infinite
@keframes box{num}
0% { left: 0px }
100% { left: (num * 30px) }
for num in (1..10)
.box{num}
animation: box + num 5s infinite
@keframes box{num}
0% { left: 0px }
100% { left: (num * 30px) }
混合(Mixins)
我们可以在混合中使用循环实现更强大的功能，例如，我们可以把表达式对作为使用插值和循环的属性。
下面，我们定义apply(), 利用所有的arguments，这样逗号分隔以及表达式列表都会支持：
apply(props)
props = arguments if length(arguments) > 1
for prop in props
{prop[0]} prop[1]
body
apply(one 1, two 2, three 3)
body
list = (one 1) (two 2) (three 3)
apply(list)
apply(props)
props = arguments if length(arguments) > 1
for prop in props
{prop[0]} prop[1]
body
apply(one 1, two 2, three 3)
body
list = (one 1) (two 2) (three 3)
apply(list)
函数(Functions)
Stylus函数同样可以包含for循环。下面就是简单使用示例：
Sum:
sum(nums)
sum = 0
for n in nums
sum += n
sum(1 2 3)
// => 6
sum(nums)
sum = 0
for n in nums
sum += n
sum(1 2 3)
// => 6
join:
join(delim, args)
buf = ''
for arg, index in args
if index
buf += delim + arg
else
buf += arg
join(', ', foo bar baz)
// => "foo, bar, baz"
join(delim, args)
buf = ''
for arg, index in args
if index
buf += delim + arg
else
buf += arg
join(', ', foo bar baz)
// => "foo, bar, baz"
后缀(Postfix)
就跟if/unless可以利用后面语句一样，for也可以。如下后缀解析的例子：
sum(nums)
sum = 0
sum += n for n in nums
join(delim, args)
buf = ''
buf += i ? delim + arg : arg for arg, i in args
sum(nums)
sum = 0
sum += n for n in nums
join(delim, args)
buf = ''
buf += i ? delim + arg : arg for arg, i in args
我们也可以从循环返回，下例子就是n % 2 == 0为true的时候返回数值。
first-even(nums)
return n if n % 2 == 0 for n in nums
first-even(1 3 5 5 6 3 2)
// => 6
first-even(nums)
return n if n % 2 == 0 for n in nums
first-even(1 3 5 5 6 3 2)
// => 6