how to define the name of a new object with a string?

Question

I would like to define a string

string<- "modelName"

That could be used to name an object later. Something like

paste0(string) <- mtcars
cat(string) <- mtcars
print(string) <- mtcars
get(string) <- mtcars

The needed result is the dataset called "modelName". None of the examples above work, obviously.

Question:

How can create one create an object which name is defined by the sourced string?

Note that this is FAQ 7.21, the most important part of which is the end where it says not to do this (as also pointed out the answer by @jdharrison) — Greg Snow, Jul 09 '14 at 16:14

jdharrison · Accepted Answer · 2014-07-09T13:01:30.633

As @Spacedman notes this is not generally the way things are done but you can use assign

string<- "modelName"

assign(string, mtcars)

> head(modelName)
                   mpg cyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1

In general it may be perferable to use sometthing like a list:

x <- list()
x[[string]] <- mtcars
> head(x$modelName)
                   mpg cyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4         21.0   6  160 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag     21.0   6  160 110 3.90 2.875 17.02  0  1    4    4
Datsun 710        22.8   4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive    21.4   6  258 110 3.08 3.215 19.44  1  0    3    1
Hornet Sportabout 18.7   8  360 175 3.15 3.440 17.02  0  0    3    2
Valiant           18.1   6  225 105 2.76 3.460 20.22  1  0    3    1

so far, i'm blissful to be ignorant why it might be bad in the grand scheme of things :) — andrey, Jul 09 '14 at 13:03
http://stackoverflow.com/questions/17559390/why-is-assign-bad covers this question — jdharrison, Jul 09 '14 at 13:07

how to define the name of a new object with a string?

Question:

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