| |
| We could either implement simple chaining for variable maps, or |
| implement generic composition classes. The former was choosen, |
| mostly because of simplicity. |
| |
| There were two implementation approaches for multiple option |
| occurences in options_and_arguments. First is store them |
| separately. The advantage is that it's easy to obtain all |
| occurences before certain position on command line. The |
| disadvantage is that we cannot return a reference to |
| vector<vector<string> > in get_all_values. It was considered |
| that if support for position-dependent options is to be |
| added, then we're be mostly interested in occurences of |
| a single option that were before some point. That's possible |
| with vector<vector<string> > storage. |