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diff --git a/files/fa/web/javascript/reference/errors/unexpected_token/index.html b/files/fa/web/javascript/reference/errors/unexpected_token/index.html new file mode 100644 index 0000000000..77fa2e06c5 --- /dev/null +++ b/files/fa/web/javascript/reference/errors/unexpected_token/index.html @@ -0,0 +1,84 @@ +--- +title: 'SyntaxError: Unexpected token' +slug: Web/JavaScript/Reference/Errors/Unexpected_token +translation_of: Web/JavaScript/Reference/Errors/Unexpected_token +--- +<div class="twocolumns"> + +</div> + +<div class="threecolumns"> +<p>{{jsSidebar("Errors")}}</p> +</div> + +<p>The JavaScript exceptions "unexpected token" occur when a specific language construct was expected, but something else was provided. This might be a simple typo.</p> + +<h2 id="Message">Message</h2> + +<pre class="syntaxbox notranslate">SyntaxError: expected expression, got "x" +SyntaxError: expected property name, got "x" +SyntaxError: expected target, got "x" +SyntaxError: expected rest argument name, got "x" +SyntaxError: expected closing parenthesis, got "x" +SyntaxError: expected '=>' after argument list, got "x" +</pre> + +<h2 id="Error_type">Error type</h2> + +<p>{{jsxref("SyntaxError")}}</p> + +<h2 id="What_went_wrong">What went wrong?</h2> + +<p>A specific language construct was expected, but something else was provided. This might be a simple typo.</p> + +<h2 id="Examples">Examples</h2> + +<h3 id="Expression_expected">Expression expected</h3> + +<p>For example, when chaining expressions, trailing commas are not allowed.</p> + +<pre class="brush: js example-bad notranslate">for (let i = 0; i < 5,; ++i) { + console.log(i); +} +// SyntaxError: expected expression, got ')' +</pre> + +<p>Correct would be omitting the comma or adding another expression:</p> + +<pre class="brush: js example-good notranslate">for (let i = 0; i < 5; ++i) { + console.log(i); +} +</pre> + +<h3 id="Not_enough_brackets">Not enough brackets</h3> + +<p>Sometimes, you leave out brackets around <code>if</code> statements:</p> + +<pre class="brush: js example-bad line-numbers language-js notranslate">function round(n, upperBound, lowerBound){ + if(n > upperBound) || (n < lowerBound){ + throw 'Number ' + String(n) + ' is more than ' + String(upperBound) + ' or less than ' + String(lowerBound); + }else if(n < ((upperBound + lowerBound)/2)){ + return lowerBound; + }else{ + return upperBound; + } +} // SyntaxError: expected expression, got '||'</pre> + +<p>The brackets may look correct at first, but note how the <code>||</code> is outside the brackets. Correct would be putting brackets around the <code>||</code>:</p> + +<pre class="brush: js example-good notranslate">function round(n, upperBound, lowerBound){ + if((n > upperBound) || (n < lowerBound)){ + throw 'Number ' + String(n) + ' is more than ' + String(upperBound) + ' or less than ' + String(lowerBound); + }else if(n < ((upperBound + lowerBound)/2)){ + return lowerBound; + }else{ + return upperBound; + } +} +</pre> + +<h2 id="See_also">See also</h2> + +<ul> + <li>{{jsxref("SyntaxError")}}</li> +</ul> |