render_delayed {rmarkdown} | R Documentation |
Delay Rendering for an Expression
Description
In a Shiny document, evaluate the given expression after the document has finished rendering, instead of during render.
Usage
render_delayed(expr)
Arguments
expr |
The expression to evaluate. |
Details
This function is useful inside Shiny documents. It delays the evaluation of its argument until the document has finished its initial render, so that the document can be viewed before the calculation is finished.
Any expression that returns HTML can be wrapped in render_delayed
.
Value
An object representing the expression.
Note
expr
is evaluated in a copy of the environment in which
the render_delayed
call appears. Consequently, no side effects
created by expr
are visible in succeeding expressions, nor are
changes to the environment after the call to render_delayed
visible
to expr
.
expr
must be an expression that produces HTML.
Examples
## Not run:
# Add the following code to an R Markdown document
div(Sys.time())
render_delayed({
Sys.sleep(3) # simulate an expensive computation
div(Sys.time())
})
div(Sys.time())
## End(Not run)