Re: COBOL Unbounded Loops: A Diatribe On Their Omission From the COBOL Standard (and a Plea for Understanding)

[David Crayford]

On 14/08/2016 2:57 AM, Paul Gilmartin wrote:
On Sat, 13 Aug 2016 09:02:28 -0500, Bill Woodger wrote:
This can be rewritten as
    while (true)
        read value
        if (value == sentinel) break;
        process value

Yet I prefer expression-oriented languages that allow constructs such as:

while read value && [ value != sentinel ]; do
     process value
     done

I prefer object-oriented languages that support exceptions with 
constructs such as:

    try
    {
        FooInputFileinput( indsn );
        BarOutputFileoutput( outdsn );
        while  ( input.read() )
        {
            // do something
        }
    }
    catch  (exception  &e )
    {
        cout  <<"Error: "  << e.what();
    }

Of course, exceptions are just like gotos but used judiciously can make 
code much easier to read and write.

But, yes, if the condition is a little more complicated, it's better to 
encapsulate
it in a function.  Legibility should be the deciding concern: which constructs
impels fewer saccades by the reader?

-- gil

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