| withVisible {base} | R Documentation |
Return both a Value and its Visibility
Description
This function evaluates an expression, returning it in a two element list containing its value and a flag showing whether it would automatically print.
Usage
withVisible(x)
Arguments
x |
an expression to be evaluated. |
Details
The argument, not an expression object, rather
an (unevaluated function) call, is evaluated in the
caller's context.
This is a primitive function.
Value
value |
The value of |
visible |
logical; whether the value would auto-print. |
See Also
invisible, eval;
withAutoprint() calls source() which
itself uses withVisible() in order to correctly
“auto print”.
Examples
x <- 1
withVisible(x <- 1) # *$visible is FALSE
x
withVisible(x) # *$visible is TRUE
# Wrap the call in evalq() for special handling
df <- data.frame(a = 1:5, b = 1:5)
evalq(withVisible(a + b), envir = df)
[Package base version 4.4.1 Index]