Fabian Groffen posted on Mon, 11 Jan 2010 08:50:30 +0100 as excerpted: > On 11-01-2010 01:25:45 +0100, Arfrever Frehtes Taifersar Arahesis wrote: >> > Can you explain the intended use of this variable, and why normal >> > DEPEND is not sufficient? >> >> PYTHON_DEPEND is intented to simplify specification of dependency on >> Python. >> >> PYTHON_DEPEND="2:2.5" is shorter than: DEPEND="|| ( >> =dev-lang/python-2.7* =dev-lang/python-2.6* =dev-lang/python-2.5* )" > > So if there is enough space to express the dependency with the current > syntax, is it worth introducing a new shorthand for it then? > > Also for this example, why does 2:2.5 expand to 2.7, 2.6 and 2.5? I > would have expected 2.0 ... 2.5. Maybe the language isn't as intuitive > then as Sebastian pointed out.
Initially intuitive, perhaps not, but reasonably easy after reading the explanation: The first position is major python version, the second if present, minimal version (within that major), so it can be read as =>version, the third if present, maximum version (within that major), so it can be read as <=. Thus, the above "2:2.5" means major version 2, minimal version 2.5 (no maximum version within that major), so 2.5+. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman
