Hello
While one can always :let &l:tw, &g:tw or &tw to a variable,
here are some observations on setting to variables and spaces.
The following work:
:let foo = 68
:exec 'set tw='.foo
but adding spaces for readability generates an error message!
:exec 'set tw = ' . foo
Setting to a variable without use of exec fails with or
without spaces -- none of the following work:
:set tw=foo
:set tw = foo
Also,
:let boo = 'set tw = 80' followed by
:exec boo fails,
but :let boo = 'set tw=80' followed by
:exec boo succeeds!
--Suresh
