像很多语言一样，javascript也支持boolean数据类型（有true和false两个值），不过特别的是，javascript中的任何对象都还隐含一个boolean值，这便是大家所说的truthy和falsy原则。我们可以很方便的使用这个隐含的属性，特别是在变量比较上（//if条件句）。掌握好这些特别的规则有助于调试我们的前端代码。truthy
# 1. Falsy valuesFalsy values is absolutely a must know for JavaScript developers. When I first started learning JS, I made the mistake of trying to memorizing what was "truthy". It always confused me. Did you know an empty array is a truthy value, that always threw me off 🤦♀...
In JavaScript, logical operators are used for boolean logic where a boolean value may be returned depending on the outcome of an expression. With the || (OR) operator, since values don't need to be explicitly true or false (they can be truthy or falsy), the operator can return non-...
🌙 The minimal & fast library for functional user interfaces - add better falsy values, and fix setting attributes for xlink:href (f… · kbrsh/moon@9b90318
getKey checks for the presence of pk and sk and throws an error if they are not present when they should be present. The code errors when the keys are falsy. This is a problem for falsy values like 0 for numeric types which are allowed in dynamo. Updated the code to allow 0 bu...
*Example: doing a POST request directly using the result ofdialog.get_values(). The following should probably be:return this.value ?? undefined;. frappe/frappe/public/js/frappe/form/controls/base_control.js returnthis.value||undefined;
core team members can create a canary releasehereor locally withgh workflow run --repo storybookjs/storybook canary-release-pr.yml --field pr=<PR_NUMBER> Greptile Summary This PR adds filtering for falsy test results in the TestProviderRender component to prevent potential undefined/null handling...
I have actually already written the rule, and it is presently in use in our codebase in Office. Rule name: no-unnecessary-falsy-condition (the name is open to debate) Summary: This rule leverages the TypeChecker to identify when explicit checks against falsy values are not needed, and ...
perf.memory = { usedJSHeapSize : 0 }; } // support of the API? if( perf.memory.totalJSHeapSize === 0 ){ console.warn('totalJSHeapSize === 0... performance.memory is only available in Chrome .') } // TODO, add a sanity check to see if values are bucketed. // If so, ...
const { window } = new JSDOM(); var $ = require("jquery")(window); var arr = [ 0, 1, '', undefined, false, 2, undefined, null, , 3, NaN ]; var filtered = $.grep(arr, Boolean); console.log(filtered); /* результат: [ 1, 2, 3 ] */С...