• Why not? (12/12) Jun 28 2019 Every C language manual/tutorial contains well-known warning
• Adam D. Ruppe (3/4) Jun 28 2019 D solved the problem a different way. It just forbids if(a = b).
• Les De Ridder (3/7) Jun 28 2019 I'm personally glad that D uses the familiar '=' operator for
• Jonathan M Davis (16/23) Jun 28 2019 One reason for it is that it makes porting code from C and other C-based
• Kagamin (3/7) Jun 28 2019 If you're a fan of pascal family languages and strict correctness

Why not? <zbigniew2011 gmail.com> writes:

Every C language manual/tutorial contains well-known warning 
about mixing '=' assignment operator and '==' equality test. 
Every now and then newcomers are warned about this - and they 
WILL do such mistakes, because it's much too easy.
During creation of new language it was so simple to fix this 
serious flaw "once for always"; simply by adopting ':=' 
assignment operator from Pascal, and by leaving - as 'equality 
testers'  - BOTH single '=' and double '==' "equal" signs.

Any idea why it didn't happen? Because "it'll spare one key-press 
when typing assignments"? Was this "saving" really that worthy - 
that it was better(?) to keep that exceptionally error-prone 
solution for next 100 years (or more)?

Adam D. Ruppe <destructionator gmail.com> writes:

On Friday, 28 June 2019 at 23:29:38 UTC, Why not? wrote:
 Any idea why it didn't happen?

D solved the problem a different way. It just forbids if(a = b). 
If you mean it, you gotta use some extra parens.

Les De Ridder <les lesderid.net> writes:

On Friday, 28 June 2019 at 23:29:38 UTC, Why not? wrote:
 During creation of new language it was so simple to fix this 
 serious flaw "once for always"; simply by adopting ':=' 
 assignment operator from Pascal, and by leaving - as 'equality 
 testers'  - BOTH single '=' and double '==' "equal" signs.

I'm personally glad that D uses the familiar '=' operator for
assignment.

Jonathan M Davis <newsgroup.d jmdavisprog.com> writes:

On Friday, June 28, 2019 9:05:54 PM MDT Les De Ridder via Digitalmars-d 
wrote:
 On Friday, 28 June 2019 at 23:29:38 UTC, Why not? wrote:
 During creation of new language it was so simple to fix this
 serious flaw "once for always"; simply by adopting ':='
 assignment operator from Pascal, and by leaving - as 'equality
 testers'  - BOTH single '=' and double '==' "equal" signs.

 I'm personally glad that D uses the familiar '=' operator for
 assignment.

One reason for it is that it makes porting code from C and other C-based
languages easier. After all, one of D's goals is for C code to be valid D
code with the same semantics or for it to not compile. That isn't
_completely_ true, but it's close, and while going with := would have still
followed that rule by causing code using = to not compile, given that the
problem with = was already solved in the same way that other languages in
the C family have generally solved it, making such a change would simply
have made porting code harder without really providing any benefit.

As I understand it, in general, Walter left things in D the same as C++
except where he felt that changes were needed. And he didn't feel that the
assignment syntax needed to be changed. As far as I recall, this is the
first time that I've ever seen anyone complain about it, so I think that
it's safe to say that the majority of D users feel the same way.

- Jonathan M Davis

Kagamin <spam here.lot> writes:

On Friday, 28 June 2019 at 23:29:38 UTC, Why not? wrote:
 During creation of new language it was so simple to fix this 
 serious flaw "once for always"; simply by adopting ':=' 
 assignment operator from Pascal, and by leaving - as 'equality 
 testers'  - BOTH single '=' and double '==' "equal" signs.

If you're a fan of pascal family languages and strict correctness 
checks, I can recommend SPARK https://www.adacore.com/sparkpro