EVOLUTION-MANAGER
Edit File: f_capture.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>R: Make a promise explicit by converting into a formula.</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="R.css" /> </head><body> <table width="100%" summary="page for f_capture {lazyeval}"><tr><td>f_capture {lazyeval}</td><td style="text-align: right;">R Documentation</td></tr></table> <h2>Make a promise explicit by converting into a formula.</h2> <h3>Description</h3> <p>This should be used sparingly if you want to implement true non-standard evaluation with 100% magic. I recommend avoiding this unless you have strong reasons otherwise since requiring arguments to be formulas only adds one extra character to the inputs, and otherwise makes life much much simpler. </p> <h3>Usage</h3> <pre> f_capture(x) dots_capture(..., .ignore_empty = TRUE) </pre> <h3>Arguments</h3> <table summary="R argblock"> <tr valign="top"><td><code>x, ...</code></td> <td> <p>An unevaluated promises</p> </td></tr> <tr valign="top"><td><code>.ignore_empty</code></td> <td> <p>If <code>TRUE</code>, empty arguments will be silently dropped.</p> </td></tr> </table> <h3>Value</h3> <p><code>f_capture</code> returns a formula; <code>dots_capture</code> returns a list of formulas. </p> <h3>Examples</h3> <pre> f_capture(a + b) dots_capture(a + b, c + d, e + f) # These functions will follow a chain of promises back to the # original definition f <- function(x) g(x) g <- function(y) h(y) h <- function(z) f_capture(z) f(a + b + c) </pre> <hr /><div style="text-align: center;">[Package <em>lazyeval</em> version 0.2.2 <a href="00Index.html">Index</a>]</div> </body></html>