Comment by 9rx

6 days ago

Is it? "Statement", defined by the dictionary as "the expression of an idea or opinion through something other than words.", seems quite apt. Symbols may end up resembling words, which perhaps is your contention, but technically they are only symbols.

Best I can tell, all usable definitions surrounding "Command" seem to suggest an associated action, which isn't true of all statements in imperative programming.

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9rx

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lmm  5 days ago

> Best I can tell, all usable definitions surrounding "Command" seem to suggest an associated action, which isn't true of all statements in imperative programming.

The defining characteristic of a programming "statement" is that it can perform some action (even if not all of them do), whereas statements in the usual everyday sense are inert. So it's not a good term.

  • 9rx  5 days ago

    > The defining characteristic of a programming "statement" is that it can perform some action

    Given a declaration "statement" such as:

         int x;

    What is the expected action? Memory allocation... I guess? Does any compiler implementation actually do that? I believe, in the age of type systems being all the rage, one would simply see that as a type constraint, not as a command to act upon.

    Expressing an idea (the values used henceforth should be integers) seems more applicable, no?

    • lmm  5 days ago

      > Given a declaration "statement" such as:

      > int x;

      > What is the expected action?

      In a language that requires you to declare variables before you use them, it clearly does something - you couldn't do "x = 5;" before, and now you can. If you're trying to understand the program operationally (and if you're not then why are you thinking about statements?) it means something like "create a variable called x", even if the implementation of that is a no-op at the machine code level.

      > I believe, in the age of type systems being all the rage, one would simply see that as a type constraint, not as a command to act upon.

      But in that case by definition one would not be seeing it as a statement! Honestly to me it doesn't really matter whether "int x;" is an expression, a statement, or some mysterious third thing (in the same way that e.g. forward declaring a function isn't a statement or an expression). When we're talking about the distinction between statements and expressions we're talking primarily about statements like "x = x + 1;", which really can't be understood as a statement in the everyday English sense.

      > Memory allocation... I guess? Does any compiler implementation actually do that?

      Toy/research or embedded compilers do yes.