package.json version ^ meaning code example

Example 1: package.json tilde vs caret

~version “Approximately equivalent to version”, will update you to all future patch versions, without incrementing the minor version. ~1.2.3 will use releases from 1.2.3 to <1.3.0.

^version “Compatible with version”, will update you to all future minor/patch versions, without incrementing the major version. ^2.3.4 will use releases from 2.3.4 to <3.0.0.

Example 2: what is package.json

metadata specific to the project
a web application, Node.js module, or even just a plain JavaScirpt library. 
identifies the project and acts as a baseline for users and contributors 
to get information about the project.
contains a collection of any given project's dependencies

Example 3: npm version notation

1.2.3 => 1.2.3 (Matching exactly same version)
~1.2.3 => >=1.2.3 && < 1.3.0 (Matching minor version)
^1.2.3 => >=1.2.3 && < 2.0.0 (Matching major version)

Example 4: package.json version

$(node -pe 'require(\"./package.json\")[\"version\"]')