composer.json install code example
Example 1: php composer update
php composer.phar update
Example 2: what is ^ in version composer.json
Caret Version Range (^)
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For example ^1.2.3 is equivalent to >=1.2.3 <2.0.0 as none of the
releases until 2.0 should break backwards compatibility.
For pre-1.0 versions it also acts with safety in mind and treats
^0.3 as >=0.3.0 <0.4.0
Tilde Version Range (~)
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The ~ operator is best explained by example: ~1.2 is equivalent
to >=1.2 <2.0.0, while ~1.2.3 is equivalent to >=1.2.3 <1.3.0
Example 3: composer add package
composer require name-of-package