Logic in Templates | Web Development with Jade

Built-in logical operators

Writing JS can start to look ugly and doesn't really match with the indentation-based syntax that Jade uses, so we have several built-in logical operators that do the same thing, but are easier to write.

Here are a few examples:

If / else / else if

Jade	HTML
- name = "Bob" if name == "Bob" h1 Hello Bob else if name == "Joe" h1 Hello Joe else h1 My name is #{name}	<h1>Hello Bob</h1>

Unless

Jade also provides unless which is equivalent to if (!(expr)), as illustrated in the following code snippet:

Jade	HTML
- name = "Bob" unless name == "Bob" h1 My name is #{name} else h1 Hello Bob	<h1>Hello Bob</h1>

Cases

Jade	HTML
- name = "Bob" case name when "Bob" p Hi Bob! when "Alice" p Howdy Alice! default p Hello #{name}!	<p>Hi Bob!</p>

Each loops

Each is used for iterating over arrays and objects and is written in the following syntax:

each VAL[, KEY] in OBJ

An example is given in the following code snippet:

Jade	HTML...

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Web Development with Jade

By : Sean Lang

Web Development with Jade

By: Sean Lang

Overview of this book

Built-in logical operators

If / else / else if

Unless

Cases

Each loops

Web Development with Jade

By : Sean Lang

Web Development with Jade

By: Sean Lang

Overview of this book

Built-in logical operators

If / else / else if

Unless

Cases

Each loops

Confirmation

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