Ruby

Currently, output warning if local variable name is _1.

# warning: `_1' is used as numbered parameter
_1 = 42

However, if parameter name is _1, no output warning is issued.

# Actual behavior
# no warning
def hoge(_1);
end

If local variable _1 causes a syntax error in Ruby 3.0(or later ?), I think it is better to output a warning even if you use argument name _1.

# Expected behavior
# warning: `_1' is used as numbered parameter
def hoge(_1);
end