在KRL中,我想检测变量是数组还是散列,以便我知道是否需要在其上使用解码或编码运算符。这可能吗?
我想做这样的事情:
my_var = var.is_array => var.decode() | my_var
答案 0 :(得分:3)
<强>更新强> 执行此操作的最佳方法是使用 typeof()运算符。这是答案以来的新内容,但随着变量的早期解释,答案中列出的旧方式将不再有效。
检查数据的另一个有用的运算符是 isnull()
myHash.typeof() => "hash"
myArray.typeof() => "array"
...
答案 1 :(得分:2)
我弄清楚如何检测数据结构类型的唯一方法是强制转换为字符串,然后检查生成的指针字符串是否包含单词“array”或“hash”。
'One liner'
myHashIsHash = "#{myHash}".match(re/hash/gi);
myHashIsHash将为true / 1
为展示概念而构建的示例应用
ruleset a60x547 {
meta {
name "detect-array-or-hash"
description <<
detect-array-or-hash
>>
author "Mike Grace"
logging on
}
global {
myHash = {
"asking":"Mike Farmer",
"question":"detect type"
};
myArray = [0,1,2,3];
}
rule detect_types {
select when pageview ".*"
pre {
myHashIsArray = "#{myHash}".match(re/array/gi);
myHashIsHash = "#{myHash}".match(re/hash/gi);
myArrayIsArray = "#{myArray}".match(re/array/gi);
myArrayIsHash = "#{myArray}".match(re/hash/gi);
hashAsString = "#{myHash}";
arrayAsString = "#{myArray}";
}
{
notify("hash as string",hashAsString) with sticky = true;
notify("array as string",arrayAsString) with sticky = true;
notify("hash is array",myHashIsArray) with sticky = true;
notify("hash is hash",myHashIsHash) with sticky = true;
notify("array is array",myArrayIsArray) with sticky = true;
notify("array is hash",myArrayIsHash) with sticky = true;
}
}
}
示例应用在运行中!