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Comment by rtkwe | Hacker News Reader

It's purpose is much the same as Maple or R a language designed with mathematics and stats. The standard library is just one of the peculiarities of how Wolfram decided to design his language. Instead of using libraries like R it's all built in. Beneath that it's not so terribly odd being a mostly functional language with a standard library that covers maths requirements.

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Beyond surface similarities like an emphasis on data transformation over side-effects, I wouldn't call Mathematica a functional language. It's much better classified as a term rewriting language: https://en.wikipedia.org/wiki/Category:Term-rewriting_progra...

Then I guess you don't call Lisp a functional language either?

The syntactical building blocks might be similar but the execution model differs. While you could obviously achieve any sort of term evaluation with a metainterpreter, the TRS in Mathematica offers a rather smart rewriting system.

It can easily express things like associative and commutative operators (esp. useful if you have a pattern that matches on a use of that operator), and alternate evaluation orders (outside-in, mixed, lazy, held, &c). These are hard to trivially implement w/o very different kind of interpreter.

In this sense, most Lisp implementations pick a static evaluation strategy and leave implementing alternatives to a metainterpreter, which isn't exactly what's happening in Mathematica.

Lisp's evaluation strategy is based on a very particular category of rewriting systems known as the lambda calculus. Mathematica's is an abstract rewrite system with a broad set of evaluation strategies that are not easily represented in the lambda calculus (without first implementing a term rewriting system).

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