expressions

Especially complicated expressions within matrices (or things like that which quickly turn into a jumbled mess in TeX).

And then when you go back to a language not based on S-expressions you'll really miss them.

The formal specifications are just assertions - they are Boolean expressions that express properties of the solution.

It is these page templates that are still stored on disk as s-expressions in the C++ version.

By this time, his facial expressions show that he also knows he is kicking ass.

The whole notion of programmable programming language that comes with Lisp tradition (which includes s-expressions).

It's easier to transform your expressions into a useful form from a guaranteed, proper SSA than from a simple tree representation.

Even worse are mixtures of signed and unsigned operands in expressions; luckily, C compilers tend to have reasonably decent warnings about that.

Python's design choices (imperative, untyped, interpreted, etc.) are just as ideological as Lisp's s-expressions.

Another thing you'll get for free from an SSA - nice ternary expressions reconstructed (even if the original code was using ifs).

Do you think I would have done something as heavy-handed as compile s-expressions at runtime if it weren't necessary?

To get from stack operations to expressions, I just symbolically evaluate the stack, creating temporary variables as I go.

For example common expressions used over and over like "nature you scary" should be given a huge penalty hit.

It would be more appropriate for there to be an entirely separate "expressions" standard for encoding various emoticon systems (there's several) and providing a standard iconography.

I am completely unfamiliar with Perl and its regular expressions, but from your article and this comment I get the impression that they are Turing-complete, which would mean they're capable of describing any formal language as well as doing any "doable" computation.

That is, if you try to model this type of system to be capable of an if statement and Boolean expressions, you really end up "back at the beginning" of digital computing, with an environment that strains to produce a simple state machine.