These functions are intended to provide a better "duality" between the name of variables in both R and tcl, including for function calls. It is possible to define a variable with the same name in R and tcl (the content is identical, but copied and coerced in the two respective environments). It is also possible to get the value of a tcl variable from R, and to call a R function from within tcl. These features are provided in the tcltk package, but Tcl variable usually have different internal names as R equivalents.
makeTclNames(names, unique = FALSE)
tclFun(f, name = deparse(substitute(f)))
tclGetValue(name)
tclSetValue(name, value)
tclVarExists(name)
tclVarFind(pattern)
tclVarName(name, init = "", keep.existing = TRUE)Arguments
- names
Transform names so that they are valid for variables in Tcl.
- unique
Should these names be unique in the vector?
- f
An R function. currently, do no support functions with arguments.
- name
The name of a variable.
- value
The value to place in a variable.
- pattern
A pattern to search for.
- init
Initial value to use when creating the variable.
- keep.existing
If the tcl variable already exist, should we keep its content?
Value
Most of these functions return a 'tclVar' object.
Details
These functions are similar to tcltk::tclVar() from package tcltk, except
for the following change: here, it is possible to propose a name for the
created tcl variable, or to set or retrieve the content of a tcl variable
that is not mirrored in R.
See also
Examples
if (FALSE) { # \dontrun{
# These cannot be run by examples() but should be OK when pasted
# into an interactive R session with the tcltk package loaded
# Tcl functions and variables manipulation
tclVarExists("tcl_version")
tclVarExists("probably_non_existant")
tclVarFind("tcl*")
# Using tclVarName() and tclGetValue()...
# intented for better match between R and Tcl variables
Test <- tclVarName("Test", "this is a test!")
# Now 'Test' exist both in R and in Tcl... In R, you need to use
tclvalue(Test) # to retrieve its content
# If a variable already exists in Tcl, its content is preserved using
# keep.existing = TRUE
# Create a variable in Tcl and assign "just a test..." to it
tclSetValue("A_Variable", "just to test...")
# Create the dual variable with same name
A_Variable <- tclVarName("A_Variable", "something else?")
tclvalue(A_Variable) # Content of the variable is not changed!
# If you want to retrieve the content of a Tcl variable,
# but do not want to create a reference to it in R, use:
tclSetValue("Another_Variable", 1:5)
tclGetValue("Another_Variable") # Get its content in R (no conversion!)
tclSetValue("Another_Variable", paste("Am I", c("happy", "sad"), "?"))
tclGetValue("Another_Variable") # Get its content in R (no conversion!)
} # }