Re: pattern bugs and comment on intuitive syntax for the

*To*: mathgroup at smc.vnet.net*Subject*: [mg115160] Re: pattern bugs and comment on intuitive syntax for the*From*: Murray Eisenberg <murray at math.umass.edu>*Date*: Mon, 3 Jan 2011 03:55:22 -0500 (EST)

Have you sent these bugs to support at wolfram.com? That's where bug reports should go. Unless, that is, these are just issues as to how _you_ think Mathematica "ought" to behave vs. how it actually behaves. On 1/2/2011 4:56 AM, Richard Fateman wrote: > Guess the results. > > x+3 /. x+c___ -> aha[c] > x /. x+c___ -> aha[c] > x /. x+c___:0 -> aha[c] > > compare to > > x+y+3 /. x+y+c___ -> aha[c] > x+y /. x+y+c___ -> aha[c] > x+y /. x+y+c___:0 -> aha[c] > x+y+a+b /. x+y+c___ :> aha[c] > x+y+a+b /. x+y+c___ :> aha[Plus[c]] > x+y /. x+y+c___ :> aha[Plus[c]] > > > > I think the requirement for the :0 represents a bug. Maybe the > need for the Plus[], too. The treatment of NullSequences within > a Flat operator could be different, leaving an operator around. > > ............ > > Another item. really, syntax. > > define > > GreaterThan[q_]:= #>q& > gt2=GreaterThan[2] (* a function of one argument. > is that argument> 2? *) > > > mm[2, 10] /. mm[q_, s_?GreaterThan[q]] :> aha[q, s] > > doesn't give aha.. > > > mm[2, 10] /. mm[q_, s_?gt2] :> aha[q, s] > > does give aha > > this works, though. > mm[2, 10] /. mm[q_, s_?(GreaterThan[q])] :> aha[q, s] > > I love that intuitive syntax. None of that excess > parentheses and stuff. (sarcasm) > > This error would have been > much more apparent in Lisp. > > happy new year. > > > > -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305