Compare Opal version with the provided one. Note that a request must have been done in order to have a non-null Opal version.
opal.version_compare(opal, version)Opal object.
The semantic version string to be compared.
>0 if Opal version is more recent, 0 if equals, <0 otherwise.
if (FALSE) {
o <- opal.login('administrator','password', url = 'https://opal-demo.obiba.org')
opal.version_compare(o, "2.6.0")
opal.logout(o)
}