[ruby/logger] Prefer String#[0, 1] over [0..0]
[0..0] internally creates an extra Array object, and so is slower and much more memory consuming
https://github.com/ruby/logger/commit/20616ad34a
Added by matsuda (Akira Matsuda) about 3 years ago
[ruby/logger] Prefer String#[0, 1] over [0..0]
[0..0] internally creates an extra Array object, and so is slower and much more memory consuming
https://github.com/ruby/logger/commit/20616ad34a