Re: Length of a held expression
- To: mathgroup at smc.vnet.net
- Subject: [mg96565] Re: [mg96524] Length of a held expression
- From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
- Date: Mon, 16 Feb 2009 06:59:54 -0500 (EST)
- References: <200902150823.DAA08017@smc.vnet.net>
I don't know whether this will suit your purpose (because I do not know what your purpose is) but by far the simplest way to get what you appear to want is: b = Sequence[1, 2]; Block[{b}, Length[{b, 3}]] 2 Andrzej Kozlowski On 15 Feb 2009, at 09:23, Nikolaus Rath wrote: > Hello, > > How can I get the length of a list in a Hold[] expression? I.e. if > > b = Sequence[1,2]; > > then I want the length of {b,3} given as 2. But > > Length[{b,3}] > > gives me the length after splicing in b (which is 4), while > > Length[Hold[{b,3}]] > > gives me the length of the hold expression (which is 1). > > > Anyone able to help? > > > Best, > > -Nikolaus > > -- > =C2=BBTime flies like an arrow, fruit flies like a Banana.=C2=AB > > PGP fingerprint: 5B93 61F8 4EA2 E279 ABF6 02CF A9AD B7F8 AE4E 425C >
- References:
- Length of a held expression
- From: Nikolaus Rath <Nikolaus@rath.org>
- Length of a held expression