Changes between Initial Version and Version 1 of Ticket #23204, comment 22


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Timestamp:
07/20/17 00:26:55 (4 years ago)
Author:
saraedum
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  • Ticket #23204, comment 22

    initial v1  
    2020> }}}
    2121> What I am saying is this is really (relatively) expensive for something that is almost certainly going to be implemented. If your category has morphisms such that you cannot effectively simplify a composition `f \circ g` to a single map `h`, then I don't see how you would have enough (generic) information to check that the composition is injective/surjective. So I doubt this would ever get used.
    22 I do not understand how this relates to `_composition_`. The point here is simply that in the category of Rings, a morphism that has a domain as its field, knows that it is injective. However, we can not so easily turn the composition into one morphism.
     22I do not understand how this relates to `_composition_`. The point here is simply that in the category of Rings, a morphism that has a field as its domain, knows that it is injective. However, we can not so easily turn the composition into one morphism.
    2323
    2424> > > No bare exceptions.