Re: HoldFirst confusion
- To: mathgroup at smc.vnet.net
- Subject: [mg65537] Re: HoldFirst confusion
- From: Jon Harrop <usenet at jdh30.plus.com>
- Date: Thu, 6 Apr 2006 06:53:16 -0400 (EDT)
- References: <email@example.com>
- Sender: owner-wri-mathgroup at wolfram.com
Yaroslav Bulatov wrote:
> The following gives an error
> f = 5; f[a_] = a
> Set is HoldFirst, so why does it evaluate it's first argument f[a_]?
Conversely, why do the attributes of Set and SetDelayed indicate that they
hold their first argument when the kernel evaluates it.
On a related note, how can you define and use a downvalue that matches
g[1+2] without evaluating the 1+2?
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
Prev by Date:
Speed: Inner MUCH slower than dot product??
Next by Date:
Re: HoldFirst question
Previous by thread:
Next by thread:
Re: Re: HoldFirst confusion