GCC SC approves inclusion of Algol 68 Front End

C's «static» and «auto» also come from PL/I. Even though «auto» has never been used in C, it has found its place in C++.

C also had a reserved keyword, «entry», which had never been used before eventually being relinquished from its keyword status when the standardisation of C began.

The "natural inverse" relationship between "address-of" and indirect addressing is only partial.

You can apply the "*" operator as many times you want, but applying "address-of" twice is meaningless.

Moreover, in complex expressions it is common to mix the indirection operator with array indexing and with structure member selection, and all these 3 postfix operators can appear an unlimited number of times in an expression.

Writing such addressing expressions in C is extremely cumbersome, because they require a great number of parentheses levels and it is still difficult to see which is the order in which they are applied.

With a postfix indirection operator no parentheses are needed and all addressing operators are executed in the order in which they are written.

So it is beyond reasonable doubt that a prefix "*" is a mistake.

The only reason why they have chosen "*" as prefix in C, which they later regretted, was because it seemed easier to define the expressions "*++p" and "*p++" to have the desired order of evaluation.

There is no other use case where a prefix "*" simplifies anything and for the postfix and prefix increment and decrement it would have been possible to find other ways to avoid parentheses and even if they were used with parentheses that would still have been simpler than when you have to mix "*" with array indexing and with structure member selection. Moreover, the use of "++" and "--" with pointers was only a workaround for a dumb compiler, which could not determine by itself whether it should access an array using indices or pointers. Normally there should be no need to expose such an implementation detail in a high-level language, the compiler should choose the addressing modes that are optimal for the target CPU, not the programmer. On some CPUs, including the Intel/AMD CPUs, accessing arrays by incrementing pointers, like in the old C programs, is usually worse than accessing the arrays through indices (because on such CPUs the loop counter can be reused as an index register, regardless of the order in which the array is accessed, including for accessing multiple arrays, avoiding the use of extra registers and reducing the number of executed instructions).

With a postfix "*", the operator "->" would have been superfluous. It has been added to C only to avoid some of the most frequent cases when a prefix "*" leads to ugly syntax.

Burroughs used an Algol60 derivative (not '68)

Algol60 had call by name, Algol68 doesn't really, it does have "proceduring" which creates a function to call when you pass an expression to a parameter that's a function pointer that has no parameters, you can use that to sort of do something like call by name but the expense is more obvious

> You can apply the "*" operator as many times you want, but applying "address-of" twice is meaningless.

This is due to the nature of lvalue and rvalue expressions. You can only get an object where * is meaningful twice if you've applied & meaningfully twice before.

    int a = 42;
    int *b = &a;
    int **c = &b;

I've applied & twice. I merely had to negotiate with the language instead of the parser to do so.

> and all these 3 postfix operators can appear an unlimited number of times in an expression.

In those cases the operator is immediately followed by a non-operator token. I cannot meaningfully write a[][1], or b..field.

> The only reason why they have chosen "*" as prefix in C, which they later regretted, was because it seemed easier to define the expressions "++p" and "p++" to have the desired order of evaluation.

It not only seems easier it is easier. What you sacrifice is complications is defining function pointers. One is far more common than the other. I think they got it right.

> With a postfix "*", the operator "->" would have been superfluous.

Precisely the reason I dislike the Pascal**.Style. Go offers a better mechanism anyways. Just use "." and let the language work out what that means based on types.

I'm offering a subjective point of view. I don't like the way that looks or reads or mentally parses. I'm much happier to occasionally struggle with function pointers.