Re: Languages that are hard to parse

Hans-Peter Diettrich <DrDiettrich@compuserve.de> writes:
>Henry Spencer wrote:
>>
>> Our moderator writes:
>> >[...The reason that PL/I doesn't have
>> >reserved words is that COBOL has a huge list, so that programmers either
>> >need to keep a chart of them on the office wall to consult every time they
>> >invent a new name, or be sure every name includes a hyphen or digit to
>> >be sure it doesn't collide with one. -John]
>>
>> Actually, it's worse than that. The usual approach is to keep a chart on
>> the wall of the *keywords* that have hyphens in them -- there are some --
>> and always put at least one hyphen in your names. The hyphenated-keywords
>> chart is a lot more manageable than the full keywords chart.
>
>Perhaps the keyword issue only is related to a specific lexer/parser
>philosophy? I'm no more familiar with COBOL, but in other programming
>languages many keywords have a special meaning only in specific
>context.


Back in the era of '80s 8-bit micros with built-in BASIC, a difference
of the Oric Atmos ("we use Microsoft BASIC!"), compared to other
machines like Sinclair/Timex of the time, was that you could not use
reserved words *anywhere* in your program (not even as part of other
words).


No much problem with RANDOMIZE, but you couldn't have a variable named
"SCORE" because "OR" was reserved...
--
-- zvr --
-- +---------------------------+ Alexios Zavras (-zvr-)
        | H eytyxia den exei enoxes | zvr@pobox.com
        +-----------------------zvr-+
[COBOL has the same problem. The huge list of reserved words is reserved
everywhere. -John]

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