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coerced to a base::logical(), is TRUE or FALSE. We use
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<h1>Truthy and falsy values</h1>
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<small class="dont-index">Source: <a href="https://github.com/rstudio/shiny/blob/HEAD/R/utils.R" class="external-link"><code>R/utils.R</code></a></small>
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<div class="hidden name"><code>isTruthy.Rd</code></div>
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</div>
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<div class="ref-description">
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<p>The terms "truthy" and "falsy" generally indicate whether a value, when
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coerced to a <code><a href="https://rdrr.io/r/base/logical.html" class="external-link">base::logical()</a></code>, is <code>TRUE</code> or <code>FALSE</code>. We use
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the term a little loosely here; our usage tries to match the intuitive
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notions of "Is this value missing or available?", or "Has the user provided
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an answer?", or in the case of action buttons, "Has the button been
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clicked?".</p>
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</div>
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<div id="ref-usage">
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<div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">isTruthy</span><span class="op">(</span><span class="va">x</span><span class="op">)</span></span></code></pre></div>
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</div>
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<div id="arguments">
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<h2>Arguments</h2>
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<dl><dt>x</dt>
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<dd><p>An expression whose truthiness value we want to determine</p></dd>
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</dl></div>
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<div id="details">
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<h2>Details</h2>
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<p>For example, a <code>textInput</code> that has not been filled out by the user has
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a value of <code>""</code>, so that is considered a falsy value.</p>
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<p>To be precise, a value is truthy <em>unless</em> it is one of:</p><ul><li><p><code>FALSE</code></p></li>
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<li><p><code>NULL</code></p></li>
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<li><p><code>""</code></p></li>
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<li><p>An empty atomic vector</p></li>
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<li><p>An atomic vector that contains only missing values</p></li>
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<li><p>A logical vector that contains all <code>FALSE</code> or missing values</p></li>
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<li><p>An object of class <code>"try-error"</code></p></li>
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<li><p>A value that represents an unclicked <code><a href="actionButton.html">actionButton()</a></code></p></li>
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</ul><p>Note in particular that the value <code>0</code> is considered truthy, even though
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<code>as.logical(0)</code> is <code>FALSE</code>.</p>
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<nav id="toc" data-toggle="toc" class="sticky-top"><h2 data-toc-skip>Contents</h2>
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<p></p><p>Developed by Winston Chang, Joe Cheng, JJ Allaire, Carson Sievert, Barret Schloerke, Yihui Xie, Jeff Allen, Jonathan McPherson, Alan Dipert, Barbara Borges.</p>
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<p></p><p>Site built with <a href="https://pkgdown.r-lib.org/" class="external-link">pkgdown</a> 2.0.7.</p>
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