character string as object name

b is character string:

as.name(b)

`MSFT$MSFT.Adjusted`

Note the backticks: that is a valid (if non-syntatatic) name, but you 
don't have an object of that name.

Can someone please tell me why the following (last line) doesn't work (as I 
expect it to :-)

The question is rather why you are misinformed about how it works.
Since you didn't explain how you think it does work, we have little 
idea what your error was.  If it helps,

MSFT$MSFT.Adjusted

is a call (to `$`).

It also helps to explain what you are trying to do rather than just 
what you did.

library(quantmod)
a = getSymbols("MSFT",from="2009-3-01")
a
MSFT
eval(as.name(a))
MSFT$MSFT.Adjusted
b=paste(a,'$MSFT.Adjusted',sep='')
b
eval(as.name(b))

Why does this last line not work the way the earlier eval does?

Thanks.

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Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
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