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0 pointsubernostrum12y ago0 comments

am a fan of strongly-typed languages

Nit-pick: suspect you are actually a fan of statically-typed languages. Python is a strongly-typed language, but not statically-typed.

(general easy way to tell them apart: in a statically-typed language, both the name and the value bound to it have a type, and those types must match; in a dynamically-typed language only the value has a type; in a weakly-typed language, operations on incompatible types are permitted, and they may be coerced for compatibility; in a strongly-typed language, operations on incompatible types are an error -- usually at compile-time or equivalent for statically-typed, usually run-time for dynamically-typed)

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3 comments · 1 top-level

masklinn12y ago· 2 in thread

> Nit-pick: suspect you are actually a fan of statically-typed languages.

And probably closer to "statically-but-not-too-statically-typed-because-really-more-than-my-language-of-choice-is-too-much" languages. Self-avowed fans of "statically-typed languages" (usually java or C#) rarely consider giving up nulls and casts.

meowface12y ago

In some cases, Java is more weakly typed than Python or Ruby.

Java:

System.out.println("abc" + 5); -> "abc5"

Python:

print "abc" + 5 -> TypeError: cannot concatenate 'str' and 'int' objects

Ruby:

puts "abc" + 5 -> TypeError: can't convert Fixnum into String

masklinn12y ago

And here we can see the issues and clusterfucks of the completely undefined and arbitrary "concept" of "weak" (conv. strong) typing: java's behavior here is well-defined, simple and statically typed, there's no more type loss than when doing `5 + 1.0` in Ruby or Python.

Why do you find implicitly converting an int (/Fixnum) to a float (/Float) more palatable, when they have completely different internal representations, domains of definition, precisions, operational semantics and potential pitfalls?

And what about Python's `"foo" * 3`? Hell, what about this:

    > class Fixnum
    >   def to_str
    >     self.to_s
    >   end
    > end
    => nil
    > "5" + 3
    => "53"

so "strongly typed" it has a protocol for implicit string conversion.

But wait, there's more without even bothering with overrides:

    > a = [1, 2, 3]
    => [1, 2, 3]
    > a[1.4]
    => 2

floating-point index to an array? no problem.

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