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Re: A tiny self-hosting compiler used for teaching

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On Tue, 25 Aug 2026 08:05:06 +0200, Michael Lehn
<michael.lehn@uni-ulm.de> wrote:


>The main motivation for A Better C is actually quite mundane. When teaching C,
>I always found declarations unnecessarily difficult to explain. For example:
>
>    int *a[10];    // array of 10 pointers to int
>    int (*b)[10];  // pointer to an array of 10 ints
>
>There is a perfectly consistent logic behind C declarations: you declare an
>object in a form resembling how it is used. But for beginners this means that
>they already need to understand operator precedence — in particular that
>postfix operators bind more strongly than prefix operators — just to read a
>declaration.
>
>I learned Pascal before C myself, and always found Pascal declarations easier
>to read because you can essentially read them from left to right.


I also learned Pascal before C, and I always have preferred
Pascal-like syntax to the line noise that is typical of C.  Ironically
most of my career was spent using C++, SQL and Scheme.


IMO, the main reasons that Pascal declarations were easier are:

  1) variable names are not intermixed with their types

  2) complex types generally require one or more type declarations
     and can't be declared inline in a variable declaration

WRT your examples (and ignoring array base issues), in Pascal the
array of pointers is no problem /because/ the base type of the array
is simple, however the pointer to array can't be declared in one step
because the array itself is not a simple type.

  type
    tenInts = array [1..10] of integer;
  var
    a : array [1..10] of ^integer; { array of 10 pointers to int }
    b : ^tenInts;                  { pointer to array of 10 ints }


Yes, reading the declaration for 'b', you do have to go search out the
declaration of 'tenInts', but what you don't have to do is decipher a
string of line noise to understand the type.

Of course, in C you could typedef the array and declare 'b' as a
pointer to it - but most programmers would never think to do that with
such a "simple" declaration.  Few even would bother declaring 'b' a
"pointer to array of int" when "pointer to int" will work just as
well.
[ignoring potential for error checking by the compiler.]

And, of course, if you want a Pascal-like language with more
functional parity to C there were/are extended and OO Pascals, and
derivatives like Modula 2, 2+, 3, etc.


>That is almost the whole idea behind A Better C: it is basically C, but with
>declarations following a Pascal-like logic. Since `^` already has a meaning in
>C, I used `->` for pointers.

Yeah ... but what do the declarations look like?  Unless you totally
changed the syntax, just changing what token(s) denote a "pointer" or
a "dereference" operation is no more helpful than is the original C.

YMMV.

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Re: A tiny self-hosting compiler used for teaching Michael Lehn <michael.lehn@uni-ulm.de> - 2026-08-25 08:05 +0200
  Re: A tiny self-hosting compiler used for teaching Cóilín Nioclásín Glostéir <thanks-to@Taf.com> - 2026-09-04 21:12 +0000
  Re: A tiny self-hosting compiler used for teaching ram@zedat.fu-berlin.de - 2026-09-05 07:02 +0000
    Re: A tiny self-hosting compiler used for teaching Michael Lehn <michael.lehn@uni-ulm.de> - 2026-09-05 19:47 -0700
  Re: A tiny self-hosting compiler used for teaching George Neuner <gneuner2@comcast.net> - 2026-09-05 14:02 -0400
    Re: A tiny self-hosting compiler used for teaching Michael Lehn <michael.lehn@uni-ulm.de> - 2026-09-05 19:50 -0700
  Re: A tiny self-hosting compiler used for teaching ram@zedat.fu-berlin.de - 2026-09-05 07:02 +0000
  Re: A tiny self-hosting compiler used for teaching George Neuner <gneuner2@comcast.net> - 2026-09-05 14:02 -0400
    Re: A tiny self-hosting compiler used for teaching George Neuner <gneuner2@comcast.net> - 2026-09-07 15:23 -0400
  Re: A tiny self-hosting compiler used for teaching Michael Lehn <michael.lehn@me.com> - 2026-09-05 22:58 -0700

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