Examples

This is a collection of examples in order to quickly test/demo different functionality.

Edu Info

• simple HTML page: double click on any elements or attributes on the page to learn what they do.
• simple SVG demo: double click on any elements or attributes on the page to learn what they do.
• CSS properties, values, etc: double click on different pieces of the CSS code to learn what they do.
• CSS selectors: double click on any of the complex CSS Selectors (and animation keyframes) to get a plain English description of which elements on the page they will effect
• JS info: double click on various parts of the JavaScript code to see it's edu info/references

Friendly Errors

CORS

• 403 forbidden image

HTML

• missing doctype
• old-school doctype
• attribute casing
• attribute doesn't exist
• attribute misspelled
• attribute repeated
• attribute single quotes
• attribute missing value
• missing alt attribute
• avoid trailing slashes
• avoid mixing tabs and spaces
• element/tag does not exist
• opening tag misspelled
• opening tag missing
• closing tag missing
• tag missing bracket v1
• tag missing bracket v2
• tag missing bracket v3
• warn about bracket syntax
• combined elements
• element/tag casing
• missing src value
• id value repeated
• avoid using "ad" in class/id values
• avoid inline styling
• avoid inline scripting
• HTML basic template: missing language attribute
• HTML basic template: missing charset
• HTML basic template: missing title element

CSS

• missing closing bracket
• missing opening bracket
• missing semicolon
• missing parentheses
• missing colon
• missing at-rule name
• double colon
• colon missing space
• colon extra space
• type selector must be standard HTML element
• hex color errors
• space between ! important
• missing space between value and !important
• empty CSS rule block
• repeated selector
• uppercase selector
• shorthand property accidentally overriding
• repeated property
• invalid property
• uppercase property
• uppercase function name
• bad gradient syntax
• specificity error
• CSS rules missing selectors

JavaScript

• missing semicolon
• unecessary semicolon
• unecessary 0's
• unecessary dot
• unecessary bracket syntax
• unecessary undefined
• reassigning const variables
• undefined const variables
• unclosed regex
• invalid regex
• comment missing closing
• comment missing opening
• unmatched token, ex1
• unmatched token, ex2
• unmatched token, ex3
• missing syntax, ex1
• missing syntax, ex2
• missing syntax, ex3
• missing syntax, ex4
• missing break
• unclosed string
• expected identifier
• bad assignment
• undefined variable
• unused variable
• redefined variable
• keyword as variable name
• function missing name
• calling function declaration
• class: setter missing getter
• class: bad method definition
• class: duplicate method name
• unreachable line
• obsolete syntax
• misplaced label
• missing template string close
• declaration order
• required function scope
• invalid meta property
• instanceof error
• default value on rest param
• bad use of super
• avoid var
• avoid array constructor
• avoid object constructor
• avoid default params before regular ones
• avoid document.write
• avoid eval
• avoid using cutting edge syntax
• bad operator
• prefer isNaN
• empty block
• Math is not a function
• expecting conditional
• avoid const in for loops
• depreciated property
• typeof error
• generator missing yield