> Here's a fun exercise, write a dictionary of arrays.

Umm … ok:

my %dict = ( foo => [ 1, 2, 3 ], bar => [ 4, 5, 6 ], );

> Now write a dictionary of 2d arrays.

my %dict2d = ( foo => [ [1, 2, 3], [4, 5, 6] ], bar => [], );

It’s pretty much identical to JS. Not sure how that’s supposed to exemplify how hard it is to write Perl.

> $ alone has so many different meanings and operations depending on context.

Used as a sigil, $ always tags a scalar, a single value.

    $foo = 3;

A reference to something else is a single value.

    $bar = [qw/ apple orange banana /];

The special variable $$ is the pid of the current process, borrowed from the shell. Special variables with punctuation names have length at most one. The leading $ is the scalar sigil, and the latter is its name.

Dereferencing a reference to scalar is rarely used and looks like either

    $$baz = $quux;

or

    ${$baz} = $quux;

In a regex, $ broadly means end of line, but the exact meaning is context sensitive: possibly end of buffer, just before a newline at the end of a buffer, or end of logical line within a buffer. Where it matters, the anchors \z and \Z have less flexible meanings.

Of those, the kinda fuzzy one is $ inside a regex. The rest follow consistent, simple rules. I’m not sure what you mean by different operations on $. Am I skipping a difficult case you have in mind?

I think shells did $ for vars first, then Perl added @ and % for arrays and hashes (and then $ was refs)

> I mean, the combinations of $%@ are really astoundingly bad. $ alone has so many different meanings and operations depending on context. You won't find that sort of thing in any other language.

I kind of felt lost first getting started with Scala where I felt like there was symbol overload.

The concatenation operator is . in Perl and ~ in Raku. You could write a normal, braced foreach loop with another one inside and not use $_.

> print "[", +( join '', map { "-> $_" } @$_ ), "]" for @{$ref}

Because computers are so slow, memory is so limited and disk space is so expensive the programmer absolutely had to write it in a single line in the most convoluted way possible? Yeah, that's definitely a language fault.