Array of array of multiple strings

Question

I am trying to create an array of array of strings, something like this:

let rules : type = [
 ["N"]
 ["N", "N"]
 ["N", "N", "N"]
]

But I couldn't set the type. How can I do this?

JohnnyHK · Accepted Answer · 2016-03-01 18:49:58Z

3

Several options here. The best way to go would be as true arrays of arrays:

let rules : string[][] = [
 ["N"],
 ["N", "N"],
 ["N", "N", "N"]
];

or

let rules : Array<Array<string>> = [
 ["N"],
 ["N", "N"],
 ["N", "N", "N"]
];

You can also type it using single-element tuple types, but that's not really the intended usage of tuple types:

let rules : [string[]] = [
 ["N"],
 ["N", "N"],
 ["N", "N", "N"]
];

or

let rules : [string][] = [
 ["N"],
 ["N", "N"],
 ["N", "N", "N"]
];

or

let rules : [[string]] = [
 ["N"],
 ["N", "N"],
 ["N", "N", "N"]
];

answered Mar 1, 2016 at 18:02

JohnnyHK

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2 Comments

Or maybe Array<Array<string>>

Or Array<string[]>. Or Array<string>[]. Or [Array<string>]. Or... :)