[fpc-devel] new features and facilities

[Mark Morgan Lloyd]

David W Noon wrote:
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> On Thu, 08 Oct 2015 16:12:56 +0000, Mark Morgan Lloyd
> (markMLl.fpc-devel at telemetry.co.uk) wrote about "Re: [fpc-devel] new
> features and facilities" (in <mv64m9$95v$1 at pye-srv-01.telemetry.co.uk>):
> 
>> Ondrej Pokorny wrote:
>>
>> As Michael has said, adding an extra  else  or for that matter 
>> otherwise  would be a problem.
>>
>>> And what about the inline if? That should be backwards compatible
>>> at a first glance. And it would be a fun thing because the Delphi
>>> community has asked for it for many years and Embarcadero looks
>>> like they won't add it at all :)
>> Inline if is an ALGOL feature, and it's inexplicable why it's never
>> been in Pascal.
> 
> Indeed, it is even more succinct in C/C++:
> 
>    x = <boolean> ? <then part> : <else part>;

At which point you'll have various members of the Pascal community 
decrying it as too C-like.

> This was taken directly from ALGOL 60 and remains a very elegant feature.
> 
> However, Jensen & Wirth excluded it from the original Pascal Report.

More to the point, I don't believe it was in in Wirth's early Pascal 
compilers although it was in ALGOL-W. This is actually quite a messy 
area, since ALGOL 68 changed the syntax to add an explicit FI for 
compatibility with the statement-level IF THEN ELSE FI.

ALGOL also had inline CASE etc., and some implementations (e.g. 
Burroughs) extended this to accomodate jump tables etc. Curiously, 
Wirth's Stanford-era compilers use these liberally.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

[Opinions above are the author's, not those of his employers or colleagues]