4 ms·

In what way are they different?

• mark-r 10y ago
  In a classic call-by-reference, changes you make to the passed parameter are seen by the caller when the function returns. That doesn't happen consistently with Python.
  • markbnj 10y ago
    I think you're just using "classic" to mean the behavior of languages like C++. Under the hood there are only two ways this mechanism can function, and I don't think it helps to mix high level language semantics in when trying to explain it, as those semantics are always expressed in one of those two ways.
    • mark-r 10y ago
      I'm using "classic" to refer to the way things were done when the terms were first invented. Old languages like C or Fortran. Python uses references implicitly without ever defining the term, so it's essential to talk about the high level semantics in this case. A Python reference (implied) differs greatly from a C++ reference in that it can be rebound with the assignment operator. If you're thinking about references in C++ terms then Python will confuse you. It's important to call out the differences.
• Pica_soO 10y ago
  Im mostly experienced with the Lua Reference handling, so beware. Usually there is one global hash-table, and a local hash table. Everything (every function, every object, every string is stored once, depending on the calling situation. So passing a reference to a object is passing the reference to that one global object, until you change it, or make a local copy of it. That sounds really strange and in a way is it. It also means, that your list of objects, will not contain duplicates. It means no useless work is done to copy data. The model involved borrows basically from the concept of lazy loading and flat copys. Do work only when needed. Super difficult to explain to new users without CS background.
• monochromatic 10y ago
  With anything immutable.