Re: Top 10 most common hard skills listed on resumes...

Bart <bc@freeuk.com> writes:

On 06/09/2024 12:53, Tim Rentsch wrote:
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Bart <bc@freeuk.com> writes:
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On 05/09/2024 16:21, Waldek Hebisch wrote:
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Bart <bc@freeuk.com> wrote:
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So what exactly is different about the LHS and RHS here:
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     A = A;
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(In BLISS, doing the same thing requires 'A = .A' AIUI;  while
'A = A' is also valid, there is a hidden mismatch in indirection
levels between left and right.  It is asymmetric while in C it
is symmetric, although seem to disagree on that latter point.)

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You seem to miss the point that assigment operator is
fundamentally assymetic.

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If you've followed the subthread then you will know that nobody
disputes that assignment reads from side of '=' and writes to the
other.
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The symmetry is to do with syntax when the same term appears on
both sides of '=', the type associated with each side, and,
typically, the internal representations too.

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Maybe it would help if you would stop thinking in terms of the
word symmetry (clearly assignment is not symmetrical) and instead
think about consistency.
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In C, the meaning of an identifier or object-locating expression
depends on where it is in the syntax tree.  In some places it
means the address of the object;  in other places it means the
contents of whatever is stored in the object.

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In a HLL, a named object (ie. a variable name) is nearly always meant
to to refer to an object's value, either its current value or what
will be its new value.

BLISS is different.

Considering the point of view of a compiler writer, it's easier
to write a compiler for Bliss than for C.  In Bliss, upon seeing
an identifier, always simply put its address in a register.  If
an object's value needs to be loaded, there will be a '.' to take
the address produced by the sub-expression and fetch the word
stored at that address.  On the other hand, in C, upon seeing an
identifier, the compiler needs to consider the context of where
the identifier appears:

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You can do the same thing in a C compiler:  always load the
address of any identifier associated with the location of
value.

Sure, but that doesn't change the basic point that in C some
additional information needs to be taken into account, and
possibly additional code generated, when looking at the parse
node for an identifier.  In BLISS the action is always just
to load the address, and no other action is ever needed.