ValueQ and package
- To: mathgroup at smc.vnet.net
- Subject: [mg89912] ValueQ and package
- From: bobeuland at gmail.com
- Date: Tue, 24 Jun 2008 03:29:43 -0400 (EDT)
In a package you typically find a construct like this: If[Not[ValueQ[Cofactor::usage]], Cofactor::usage = "Cofactor[m, {i, j}] calculates the (i, j)th cofactor of matrix m." ]; My question is what the benefit of this is. Why not just use: Cofactor::usage = "Cofactor[m, {i, j}] calculates the (i, j)th cofactor of matrix m." Thanks http://bobueland.com/