Comment by djsumdog | Hacker News Reader

Comment by djsumdog | Hacker News Reader

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Yea, I like list comprehensions. I mean they make sense once you're use to reading the syntax. That's just like the following in Scala:

   foo = baz.list().filter{ bar => condition(bar) }.map(transform(_)).toList

If it's your first time looking at Scala, you'd probably be like, "What the fuck is that shit?" but as you learn the language, these types of patterns become common and make a lot of sense.

I mean it's not like weird rules in natural language. At least the grammars for computer languages are strict, with very few edge cases (compared to human/spoken language).

I hope you mean:

    foo = baz.list().filter(condition).map(transform).toList

No need to create the extra anonymous functions.

Does Scala have line continuation? I got really used to pipes from R (which I guess come from F#/Elixir), which in turn got me really comfortable with multi-line statements like:

    foo = baz.\
        list().\
        filter{ bar => condition(bar) }.\
        map(transform(_)).\
        toList

IMO this is about as readable as it gets. It's like bullet points enumerating each step in the "algorithm" that produces a `foo`.

AFAIK Javascript also uses this pattern a lot.

I think that Scala uses semicolon terminated lines so you would write something like:

    foo = baz
        .list()
        .filter{ bar => condition(bar) }
        .map(transform(_))
        .toList;

Scala doesn't require the semi-colon at the very end, but it does allow for them if you really want two statements on the same line.

Edit: and yes, that line separation works fine, both compiled and in the REPL.

BTW similar syntax in javascript, ruby, c#, etc.

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