Infix doesn't worj with precedence and grouping

*To*: mathgroup at smc.vnet.net*Subject*: [mg113629] Infix doesn't worj with precedence and grouping*From*: Dims <dims12 at hotmail.com>*Date*: Fri, 5 Nov 2010 05:12:19 -0500 (EST)

It is told in help, that Infix[expr,h,precedence,grouping] can be used to specify how the output form should be parenthesized. but actually it doesn't work: Format[EClass[x___]] := Infix[{x}, "=", 290, None] In[40]:= EClass[a, b, c] Out[40]= Infix[{a, b, c}, "=", 290, None] while In[65]:= Format[EClass[x___]] := Infix[{x}, "="] In[66]:= EClass[a, b, c] Out[66]= Infix[{a, b, c}, "="] works. So how to specify precedence for infix format? Thanks.