Duncan Murdoch wrote:
It's fairly unlikely to go away, but it's an old undocumented feature,
so use at your own risk. There are lots of other undocumented features,
but maybe no others at the lexical level. Check out src/main/gram.y if
you want to search for more at that level, and src/* if you want them at
any level.
I just had a quick browse in the source and I can't see where "**" is
defined. names.c relates ^ to the power operation in arithmetic.c but no
sign of "**":
./names.c:{"^", do_arith, POWOP, 1, 2,
{PP_BINARY2, PREC_POWER, 1}},
grepping for POWOP doesn't help.
It's not an operator like '*':
> get("**")
Error in get("**") : variable "**" was not found
> get("*")
function (e1, e2) .Primitive("*")
and there's no ** in gram.y.
searching for 'power' and quoted "**" doesn't help me either. Searching
for unquoted ** just produces too much C code to be useful.
It's got to be there somewhere!!!
Barry
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