EVOLUTION-MANAGER

Edit File: last_warnings.html

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<table width="100%" summary="page for last_warnings {rlang}"><tr><td>last_warnings {rlang}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Display last warnings</h2>

<h3>Description</h3>

<p><code>last_warnings()</code> and <code>last_messages()</code> return a list of all
warnings and messages that occurred during the last R command.
</p>
<p><code><a href="global_entrace.html">global_entrace()</a></code> must be active in order to log the messages and
warnings.
</p>
<p>By default the warnings and messages are printed with a simplified
backtrace, like <code><a href="last_error.html">last_error()</a></code>. Use <code>summary()</code> to print the
conditions with a full backtrace.
</p>

<h3>Usage</h3>

<pre>
last_warnings(n = NULL)

last_messages(n = NULL)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>n</code></td>
<td>
<p>How many warnings or messages to display. Defaults to all.</p>
</td></tr>
</table>

<h3>Examples</h3>

<p>Enable backtrace capture with <code>global_entrace()</code>:
</p>
<div class="sourceCode r"><pre>global_entrace()
</pre></div>
<p>Signal some warnings in nested functions. The warnings inform about
which function emitted a warning but they don't provide information
about the call stack:
</p>
<div class="sourceCode r"><pre>f &lt;- function() { warning("foo"); g() }
g &lt;- function() { warning("bar", immediate. = TRUE); h() }
h &lt;- function() warning("baz")

f()
#&gt; Warning in g() : bar
#&gt; Warning messages:
#&gt; 1: In f() : foo
#&gt; 2: In h() : baz
</pre></div>
<p>Call <code>last_warnings()</code> to see backtraces for each of these warnings:
</p>
<div class="sourceCode r"><pre>last_warnings()
#&gt; [[1]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `f()`: foo
#&gt; Backtrace:
#&gt;  1. global f()
#&gt;
#&gt; [[2]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `g()`: bar
#&gt; Backtrace:
#&gt;  1. global f()
#&gt;  2. global g()
#&gt;
#&gt; [[3]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `h()`: baz
#&gt; Backtrace:
#&gt;  1. global f()
#&gt;  2. global g()
#&gt;  3. global h()
</pre></div>
<p>To get a full backtrace, use <code><a href="../../base/html/summary.html">summary()</a></code>. In this case the full
backtraces do not include more information:
</p>
<div class="sourceCode r"><pre>summary(last_warnings())
#&gt; [[1]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `f()`:
#&gt; foo
#&gt; Backtrace:
#&gt;     x
#&gt;  1. \-global f()
#&gt;
#&gt; [[2]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `g()`:
#&gt; bar
#&gt; Backtrace:
#&gt;     x
#&gt;  1. \-global f()
#&gt;  2.   \-global g()
#&gt;
#&gt; [[3]]
#&gt; &lt;warning/rlang_warning&gt;
#&gt; Warning in `h()`:
#&gt; baz
#&gt; Backtrace:
#&gt;     x
#&gt;  1. \-global f()
#&gt;  2.   \-global g()
#&gt;  3.     \-global h()
</pre></div>

<p><code><a href="last_error.html">last_error()</a></code>
</p>

<hr /><div style="text-align: center;">[Package <em>rlang</em> version 1.0.6 <a href="00Index.html">Index</a>]</div>
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