But "@eval" is still a macro, so it is even better to rewrite this without that: function getfn() return function(); 1; end end const n = getfn()
On Sat, May 30, 2015 at 2:30 PM David Gold <david.gol...@gmail.com> wrote: > Something to note about Tom's method is that the name function must be > passed to gf as a symbol, unlike in the case of a macro. However, in most > cases this slight difference probably will not warrant a macro. > > > On Friday, May 29, 2015 at 8:58:56 PM UTC-4, Tom Lee wrote: >> >> You don't need to use a macro, a function can do this: >> >> julia> function gf(n::Symbol = gensym()) >> @eval function $(n)() >> 1 >> end >> end >> >> I've also made the n argument optional, with gensym creating a unique >> name by default - the newly defined function is returned by gf, so you >> don't necessarily need to know its name. And of course if you give gf >> additional arguments you can programatically construct expressions based >> those and easily $ them into the @eval block. It's all very awesome. >> >> But the point is a macro probably isn't appropriate for this type of >> thing. My understanding is that you should never use a macro if you can >> easily write an equivalent function. >> >> Cheers, >> >> Tom >> >> On Thursday, 28 May 2015 23:26:39 UTC+10, Mauro wrote: >>> >>> Like this: >>> >>> julia> macro gf(n) >>> quote >>> function $(esc(n))() >>> 1 >>> end >>> end >>> end >>> >>> julia> @gf foo >>> foo (generic function with 1 method) >>> >>> julia> foo() >>> 1 >>> >>> On Thu, 2015-05-28 at 12:06, Vasudha Khandelwal <vasudhakh...@gmail.com> >>> wrote: >>> > Can I use macros to generate functions with names passed as argument >>> to the >>> > macro? >>> >>>
