Is this number a repdigit? Challenge
A repdigit is a non-negative integer whose digits are all equal.
Create a function or complete program that takes a single integer as input and outputs a truthy value if the input number is a repdigit in base 10 and falsy value otherwise.
The input is guaranteed to be a positive integer.
You may take and use input as a string representation in base 10 with impunity.
Test cases
These are all repdigits below 1000.
1
2
3
4
5
6
7
8
9
11
22
33
44
55
66
77
88
99
111
222
333
444
555
666
777
888
999

A larger list can be found on OEIS.
Winning
The shortest code in bytes wins. That is not to say that clever answers in verbose languages will not be welcome.
Brachylog, 1 byte

=


Try it online!

This acts on integers.

From src/predicates.pl#L1151:

brachylog_equal('integer':0, 'integer':0, 'integer':0).
brachylog_equal('integer':0, 'integer':I, 'integer':I) :-
    H #\= 0,
    integer_value('integer':_:[H|T], I),
    brachylog_equal('integer':0, [H|T], [H|T]).