instance method
Array#to_h
() -> ::Hash[untyped, untyped]
[T, S] () { (Elem) -> [ T, S ] } -> ::Hash[T, S]
to_h → new_hash
to_h {|element| ... } → new_hash
array.c
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static VALUE
rb_ary_to_h(VALUE ary)
{
long i;
VALUE hash = rb_hash_new_with_size(RARRAY_LEN(ary));
int block_given = rb_block_given_p();
for (i=0; i<RARRAY_LEN(ary); i++) {
const VALUE e = rb_ary_elt(ary, i);
const VALUE elt = block_given ? rb_yield_force_blockarg(e) : e;
const VALUE key_value_pair = rb_check_array_type(elt);
if (NIL_P(key_value_pair)) {
rb_raise(rb_eTypeError, "wrong element type %"PRIsVALUE" at %ld (expected array)",
rb_obj_class(elt), i);
}
if (RARRAY_LEN(key_value_pair) != 2) {
rb_raise(rb_eArgError, "wrong array length at %ld (expected 2, was %ld)",
i, RARRAY_LEN(key_value_pair));
}
rb_hash_aset(hash, RARRAY_AREF(key_value_pair, 0), RARRAY_AREF(key_value_pair, 1));
}
return hash;
}
Returns a new hash formed from self.
With no block given, each element of self must be a 2-element sub-array; forms each sub-array into a key-value pair in the new hash:
Example
a = [['foo', 'zero'], ['bar', 'one'], ['baz', 'two']] a.to_h # => {"foo"=>"zero", "bar"=>"one", "baz"=>"two"} [].to_h # => {}
With a block given, the block must return a 2-element array; calls the block with each element of self; forms each returned array into a key-value pair in the returned hash:
Example
a = ['foo', :bar, 1, [2, 3], {baz: 4}] a.to_h {|element| [element, element.class] } # => {"foo"=>String, :bar=>Symbol, 1=>Integer, [2, 3]=>Array, {:baz=>4}=>Hash}
Related: see Methods for Converting.