| GHC is oddly particular about decimal points in "read"-ing in
| of Doubles in scientific notation. It seems that read
| "3.0e-06" is acceptable but read "3e-06" is not (both read
| "3" and read "3.0" work fine as Doubles). It's the same in
| nhc and hugs. Perhaps this is some standard somewhere that
| Perl doesn't understand?
It's true about the Haskell language too, and that's why it's true of
Read. The lexical syntax says that
10e3
means
10 e3
(i.e. two lexemes). I don't like this choice, and it could be "fixed"
in the Revised H98 report. The current production for float is
float -> decimal . decimal[(e | E)[- | +]decimal]
I guess we could change that to
exponent -> (e|E) [+|-] decimal
float -> decimal . decimal [exponent]
| decimal exponent
It's an unforced change and therefore to be regarded with
deep suspicion. I'd be interested in people's views about this.
Simon
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