Semicolon

What's a language without a semicolon? Since Egel has strict semantics but combinators may be side-effecting, it makes sense to add statements, a bit of a trivial extension, to at least give users the possibility to easily define input/output behavior. For example,

printLine "What's your name?"; let X = readLine in print "Hello, " X "!"

Which is a bit shorter than

let _ = printLine "What's your name?" in let X = readLine in print "Hello, " X "!"

But I guess that'll pay off for longer routines. The easiest manner of generating code for semicolons is therefor a let. But lijero on freenode pointed out that you can also employ a 'semicolon' combinator.

[ X _ -> X ] (let X = readLine in print "Hello, " X "!") (printLine "What's your name?")

So, there are some tradeoffs. The let sugar means I'll generate one combinator for each semicolon, the semicolon combinator needs to be added to the runtime -which I don't like- but you could, for instance, then fold that semicolon over a list.

Then, should the semicolon combinator be a built-in or generated on the fly? I don't know yet. If I had some kind of optimizing compiler, the compiler would need to know about its definition. A C++ defined combinator is a bit faster but also more a bit work.

Looks like I'll go the whole principled way of going for an explicit AST node for a statement, a transform do desugarize that, and built-in C++ combinator.

For a semicolon.