Composer. How to install a specific version of package based on user php version?

Question

I have a two version of my package: for php7 and for php5. Is it possible to make composer determine when installing the package which version of php the user has, and depending

Answer 1

Install only one composer you can access this composer with different php version

/usr/bin/php /usr/local/bin/composer
/usr/bin/php7.1 /usr/local/bin/composer
/usr/bin/php7.0 /usr/local/bin/composer