5 ms·

I often think people don't have a problem with static types and instead would miss the implicit type conversion dynamic typing provides.

• DonaldPShimoda 5y ago
  > miss the implicit type conversion dynamic typing provides Implicit type conversion is not an inherent property of dynamic typing. For example, Python does not do implicit type conversion except in arithmetic. You can't do, e.g., `4 + "hello"`. Leaving that aside, though... I'm actually not convinced implicit type conversions are much of a win, especially when it comes to types other than the simple arithmetic ones (and those can often be handled in explicit type-checking anyway, through a numerical type hierarchy). I would rather be forced to handle explicit conversion everywhere I want it than accidentally forget about some edge case and end up with an unintended implicit conversion that causes unexpected behavior at run time.
  • chriswarbo 5y ago
    > Python does not do implicit type conversion except in arithmetic. You can't do, e.g., `4 + "hello"` Interestingly, PHP uses separate operators for numerical addition (+) and string concatenation (.), so it's actually a bit more explicit than e.g. Javascript (where 'x + y' could result in normal numerical addition, or normal string concatenation, or implicit conversion to a numerical addition, or implicit conversion to a string concatenation!)
    • throw_m239339 5y ago
      > Interestingly, PHP uses separate operators for numerical addition (+) and string concatenation (.), so it's actually a bit more explicit than e.g. Javascript (where 'x + y' could result in normal numerical addition, or normal string concatenation, or implicit conversion to a numerical addition, or implicit conversion to a string concatenation!) Only because Rasmus didn't know how to design and implement a "proper" programming language. This isn't a intended feature, it just made parsing easier for him.
      • onaworkcomputer 5y ago
        Rasmus borrowed this distinction from Larry Wall, since PHP was originally implemented in Perl (which also uses + for addition and . for string concatenation). The neat thing about PHP and the + operator is that you can sometimes trick the interpreter into doing math on the underlying bytes of the string: http://dominic-mulligan.co.uk/wp-content/uploads/2015/05/SREPLSApr2016.pdf http://dominic-mulligan.co.uk/wp-content/uploads/2015/05/SRE...
      • TazeTSchnitzel 5y ago
        There's nothing improper about having a separate operator for concatenation.
        • throw_m239339 5y ago
          > There's nothing improper about having a separate operator for concatenation. Only to monopolize that operator to then have to use "->" for method call. C/C++ do that because of dereferencing. There is no need for that in PHP OO, all objects are passed by pointer to functions or methods.
          • giaour 5y ago
            Meh, other languages manage to assign multiple meanings to single tokens and depend on context to resolve ambiguity. PHP's issue here is that it refuses to do so, which is how we ended up with the backslash as a namespace delimiter.
• 89vision 5y ago
  I think scala strikes a pretty good balance here. It's statically typed, but the compiler will attempt to infer types if not explicitly defined. If you want an implicit type conversion the type conversion function needs to be defined and in scope
• david422 5y ago
  Do you mean something like passing a string to a function and later passing a number and have it still act appropriately?
  • dboreham 5y ago
    Welcome to JavaScript.
• convolvatron 5y ago
  those a pretty orthogonal issues, you can make a system arbitrarily static or dynamic with or without implicit conversion
• paskozdilar 5y ago
  I love Python because you can just do foo = "bar" and be done with it. The interpreter knows it's a string variable. But I don't really care about runtime dynamic typing - I can't wait for Go to get parametric polymorphism, interfaces and runtime type dispatching can be quite clumsy. I would be perfectly fine with typed function arguments in a Pythonic language and being able to only call functions that fit the variable type (which is what I end up doing anyway with typehints and mypy). I think Go made a right decision there - they kept the static typing but added a walrus := operator for automatic type inference. Every function has a type signature so the type inference algorithm is pretty trivial, and the language still feels like Python: result, err := FunctionThatMayFail()
  • kaba0 5y ago
    Basic type inference has been around for decades, Go isn’t responsible for it. Haskell, scala, etc had it for a long time.
    • paskozdilar 5y ago
      >Basic type inference has been around for decades, Go isn’t responsible for it. I never said it was.