Text Output
renderText(expr, env = parent.frame(), quoted = FALSE, func = NULL)Arguments
| expr | An expression that returns an R object that can be used as an
argument to cat. |
|---|---|
| env | The environment in which to evaluate expr. |
| quoted | Is expr a quoted expression (with quote())? This
is useful if you want to save an expression in a variable. |
| func | A function that returns an R object that can be used as an
argument to cat.(deprecated; use expr instead). |
Text Output
Description
Makes a reactive version of the given function that also uses
cat to turn its result into a single-element character
vector.
Details
The corresponding HTML output tag can be anything (though pre is
recommended if you need a monospace font and whitespace preserved) and should
have the CSS class name shiny-text-output.
The result of executing func will passed to cat, inside a
capture.output call.
Examples
isolate({ # renderPrint captures any print output, converts it to a string, and # returns it visFun <- renderPrint({ "foo" }) visFun() # '[1] "foo"' invisFun <- renderPrint({ invisible("foo") }) invisFun() # '' multiprintFun <- renderPrint({ print("foo"); "bar" }) multiprintFun() # '[1] "foo"\n[1] "bar"' nullFun <- renderPrint({ NULL }) nullFun() # 'NULL' invisNullFun <- renderPrint({ invisible(NULL) }) invisNullFun() # '' vecFun <- renderPrint({ 1:5 }) vecFun() # '[1] 1 2 3 4 5' # Contrast with renderText, which takes the value returned from the function # and uses cat() to convert it to a string visFun <- renderText({ "foo" }) visFun() # 'foo' invisFun <- renderText({ invisible("foo") }) invisFun() # 'foo' multiprintFun <- renderText({ print("foo"); "bar" }) multiprintFun() # 'bar' nullFun <- renderText({ NULL }) nullFun() # '' invisNullFun <- renderText({ invisible(NULL) }) invisNullFun() # '' vecFun <- renderText({ 1:5 }) vecFun() # '1 2 3 4 5' })[1] "foo"[1] "1 2 3 4 5"
See also
renderPrint for capturing the print output of a
function, rather than the returned text value.
