On Sunday, April 24, 2016 at 12:15:23 PM UTC+2, Ben Greenman wrote: > I think you want hash-clear! because I think you're using a mutable hashtable. > > > hash-clear! is for mutable hashtables (built with make-hash, added to with > hash-add!) and returns void after it updates its argument > hash-clear is for immutable hashes (build with hash or for/hash, added to > with hash-add) and returns a new hashtable -- for example: > > > (define h (hash 'a 1)) > > (define i (hash-clear h)) > > (hash-count h) > 1 > > (hash-count i) > 0 > > > > > > > > > > The notes on chaperones & impersonators are only about efficiency. They > shouldn't affect your choice. > > > > On Sun, Apr 24, 2016 at 5:11 AM, Damien Mattei <damien...@gmail.com> wrote: > hi, > > > > what is the best way to clear a hash table, hash-clear or hash-clear! ? if > the hash-table is defined in a code at top-level and used in functions as a > global variable, the issue i have is that when at REPL i use a first time my > function (that use hash-table) it's ok but when i reuse the function it > returns a wrong result as the hash-table is not redefined and cleared and has > data in it that make interfere with reuse of hash-table, so i need to clear > it ... > > i tried to read the story about chaperone and impersonator in the doc but my > english and the specificities of drracket scheme make that i do not > understand which of hash-clear or hash-clear! is more appropriate in this > case. > > > > regards, > > > > damien > > > > -- > > You received this message because you are subscribed to the Google Groups > "Racket Users" group. > > To unsubscribe from this group and stop receiving emails from it, send an > email to racket-users...@googlegroups.com. > > For more options, visit https://groups.google.com/d/optout.
thanks you thats that what i had finally use,now i had no doubts thanks Damien -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
