To do what you want, very briefly: > x.args[3] == :pi && x.args[3] = Expr(:call, :BigFloat, :pi)
This will make more sense if you look at `xdump` output to see how Exprs are structured (and `xdump` is quite handy to know about in general). Try: > xdump(:(big(3) + big(pi))) ... On Fri, Sep 19, 2014 at 9:42 AM, David P. Sanders <[email protected]> wrote: > > > El viernes, 19 de septiembre de 2014 08:34:05 UTC-5, David P. Sanders > escribió: >> >> Hi, for a package I'm writing (or, more precisely, trying to write), I >> need to do the following: >> >> Change `:(3 + pi)` >> into `:(3 + big(pi))` >> or `:(BigFloat(3) + BigFloat(pi))` >> > > I forgot to say that I need to do this so that I can perform the > calculations with different rounding modes. > > >> >> Basically I need to apply `BigFloat` to every symbol in the expression. >> (I believe that it would be sufficient to wrap `MathConst`s in `big`, but >> converting everything to BigFloat is probably a good idea.) >> >> This is my first foray into parsing etc. I'm guessing there's a package >> that allows me to do this easily -- could someone please point it out? >> Or how should I go about this? >> >> In principle the expressions could be more complicated, e.g. `(3 + pi) * >> (2.5 - e)` >> >> Thanks, >> David. >> >
