The story goes (IIRC):
He was initially hired to write a Scheme like dialect. Many applications had embedded Lisp engines, like Emacs, AutoCad, Gimp,...
But Netscape made a deal with Sun, and he was told to design something that looks syntactically like Java.
As you mentioned , are strings one important difference, because they are immutable in JS, while in Perl they are a piece of memory at your free disposal.
The lack of pure hashes is (or was?) a big problem in JS.
There are some other issues, but for me is 90% of JS just a mini Perl with Java syntax.
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery
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