This version of substitute is needed because
substitute does not
evaluate it's first argument, and it's often useful to be able to modify
a quoted call.
a quoted call
an environment, or something that behaves like an environment
(like a list or data frame), or a reference to an environment (like a
positive integer or name, see
1 2 3
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.