
Makes a reactive version of the given function that also uses
base::cat()
to turn its result into a single-element character
vector.
renderText(
expr,
env = parent.frame(),
quoted = FALSE,
outputArgs = list(),
sep = " "
)
An expression that returns an R object that can be used as an
argument to cat
.
The environment in which to evaluate expr
.
Is expr
a quoted expression (with quote()
)? This
is useful if you want to save an expression in a variable.
A list of arguments to be passed through to the implicit
call to textOutput()
when renderText
is used in an
interactive R Markdown document.
A separator passed to cat
to be appended after each
element.
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
utils::capture.output()
call.
renderPrint()
for capturing the print output of a
function, rather than the returned text value.
# NOT RUN {
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'
})
# }
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