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Re: sweet-expressions are not homoiconic
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John Cowan writes:
> If newline as a statement terminator counts as syntactically significant
> whitespace, then there are a lot bigger guns than Icon that have it,
> starting with Fortran, Cobol, and Basic, and going on to every command
> language ever created.
I'd put them in a slightly different class. They were created in
the era of punched cards (FORTRAN, COBOL) or line editors (BASIC) and so
treat the line as a natural unit. Through much of that era, there was no
such thing as a newline character; I can recall writing FORTRAN programs in
which each output line began with a format signal, directing the printer to
stay on the same line, advance one line, advance two lines, or skip to the
top of the next page.
> To bracket such languages with identation
> sensitive ones is to trivialize the concept.
I wouldn't have mentioned it at all if Wheeler hadn't used Icon as
an example in support of his argument.
> If you're worried about it, make sure all continued lines end in _,
> that's all.
Sigh. Yes, of course -- a marker character. And in FORTRAN you
can always put a C or an asterisk in column 6 of the next line. These are
evidences of _failure to achieve homoiconicity_. They are design kludges,
used to paper over the incompatibility between whitespace used for layout
and whitespace used to signal syntactic structure.
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