The Idea of Lisp

Re:The Idea of Lisp by vertex-four on Friday December 16, 2016 @11:11AM (#13194201)

The difference is that C/Java/Algol have different syntaxes for things-as-expressions and things-as-statements, and you can't put blocks in the things-as-expressions. In Rust, blocks are also expressions and so have a result (the result of the last expression in the block), so your expressions inside the if can be as complex as you like.

Since functions also have a block, and the return value of the function is the result of the block, this is much more consistent.

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Re:The Idea of Lisp by kazinator on Friday December 16, 2016 @01:44PM (#13195608)

In GNU C, you can use a brace-enclosed statement block as an expression.

Funny story; years before I became a C programmer, and at a time when I didn't yet study ISO C properly, I discovered and used this extension naturally.

I wanted to evaluate some statements where only an expression could be used so I thought, gee, come on, can't you just put parens around it to turn it into an expression and get the value of the last expression as a return value? I tried that and it worked. And of course, if it works it's good (standards? what are those?)

Then I tried using the code with a different C compiler; oops!

Anyway, this GNU C feature doesn't have as much of an impact as you might think.

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