On 07/28/2015 11:37 AM, Florian Festi wrote: > On 07/28/2015 09:43 AM, Lubos Kardos wrote: >> Support in rpm is not enough but libsolv supports rich deps since the version >> 0.6.9 too thus rich deps work also in hawkey and dnf if the version 0.6.9 or >> a newer version of libsolv is installed. > > Right now only AND and OR is supported by libsolv. Implementation of IF > ELSE is still pending. > > Also we still need to settle to a final syntax for the operators [1]. > Unfortunately there is no consensus among the other packaging formats > what to use. Right now rpm accepts 3 different styles: > * AND OR IF ELSE > * & | ? : > * && || ? : > But the final release will only support on of them. As soon as the alpha > stops eating babies that's a discussion we need to have. I think that C-style operators (&, &&) are better than verbose COBOL-style ones because they are consistent with relation operators (>, >= and so on) already used by rpm. Secondly, they don't introduce conflict with existing meaning - "Requires: foo AND bar" is valid syntax in rpm <= 4.12, equivalent to requiring three packages separately. >From C-style operators I would prefer single-character ones for two reasons: 1) Two-character operators may suggest short-circuit evaluation - "Requires: foo || bar" can be misunderstood as "require foo, or bar if and only if foo is not available", which is not how that works. There is no such problem with single-character operators. In other words, "|" and "&" operators are commutative, but "||" and "&&" are not. 2) Debian uses single-character operators. Cross-distro consistency and less confusion for people working on both Fedora and Debian is a plus. -- Mikolaj Izdebski Software Engineer, Red Hat IRC: mizdebsk -- devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/devel Fedora Code of Conduct: http://fedoraproject.org/code-of-conduct
