Ruby: Creating a hash key and value from a variable in Ruby

hash, ruby, syntax

Solution

If you want to populate a new hash with certain values, you can pass them to `Hash::[]`:

Hash["a", 100, "b", 200]             #=> {"a"=>100, "b"=>200}
Hash[ [ ["a", 100], ["b", 200] ] ]   #=> {"a"=>100, "b"=>200}
Hash["a" => 100, "b" => 200]         #=> {"a"=>100, "b"=>200}

So in your case:

Hash[id, 'foo']
Hash[[[id, 'foo']]]
Hash[id => 'foo']

The last syntax `id => 'foo'` can also be used with `{}`:

{ id => 'foo' }

Otherwise, if the hash already exists, use `Hash#=[]`:

h = {}
h[id] = 'foo'

Problem

I have a variable `id` and I want to use it as a key in a hash so that the value assigned to the variable is used as key of the hash. For instance, if I have the variable `id = 1` the desired resulting hash would be `{ 1: 'foo' }`. I've tried creating the hash with, ``` { id: 'foo' } ``` But that doesn't work, instead resulting in a hash with the symbol `:id` to `'foo'`. I could have sworn I've done this before but I am completely drawing a blank.

Original source

Related problems