Füsilier Breitlinger

Indoor European. I know #regex. I write #code (in #C or #Haskell or #Perl or #JavaScript or #bash).

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Joined 2 years ago
Cake day: November 6th, 2022
  • Füsilier Breitlinger@infosec.exchangetoProgrammer Humor@lemmy.ml•Evil Ones
    1·
    2 days ago

    @masterspace Love the confidence, but your facts could do with some work.

    • “Interpreted language” is not a thing. Interpreted vs compiled is a property of a particular implementation, not the language.
      (I wonder how you would classify lazy functional languages like Haskell. The first implementations were all interpreters because it was not clear that the well-known graph reduction technique for lazy evaluation could be compiled to native code at all.Today, hugs (a Haskell interpreter written in C) isn’t maintained anymore, but GHC still comes with both a native compiler (ghc) and an interpreter (runghc, ghci).)

    • Most implementations that employ interpretation are compiler/interpreter hybrids. It is rare to find an interpreter that parses and directly executes each line of code before proceeding to the next (the major exception being shells/shell scripts). Instead they first compile the source code to an internal representation, which is then interpreted (or, in some cases, stored elsewhere, like Python’s .pyc files or PHP’s “opcache”).

    • You can tell something is a compile-time error if its occurrence anywhere in the file prevents the whole file from running. For example, if you take valid code and add a random { at the end, none of the code will be executed (in Javascript, Python, Perl, PHP, C, Haskell, but not in shell scripts).

    • The original “lint” tool was developed because old C compilers did little to no error checking. (For example, they couldn’t verify the number and type of arguments in function calls against the corresponding function definitions.) “Linting” specifically refers to doing extra checks (some of which may be more stylistic in nature, like a /*FALLTHRU*/ comment in switch statements) beyond what the compiler does by itself.

    • If I refer to an undeclared variable in a Perl function, none of the code runs, even if the function is defined at the end of the file and never called. It’s a compile-time error (and I don’t have to install and configure a linting tool first). The same is true of Haskell.
      What’s funny to me is that Javascript copied use strict directly from Perl (albeit as a string because Javascript doesn’t have use declarations), but turned it into a runtime check, which makes it a lot less useful.