# Grammatical ambiguity around \`catch\` blocks

**URL:** <https://internals.rust-lang.org/t/grammatical-ambiguity-around-catch-blocks/4807>\
**Category:** language design\
**Created:** [February 17, 2017, 8:56pm UTC](https://internals.rust-lang.org/t/grammatical-ambiguity-around-catch-blocks/4807 "2017-02-17T20:56:51Z")\
**Posts on this page:** 1\
**Showing post:** 20

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**Author:** ![nikomatsakis](https://sea2.discourse-cdn.com/flex002/user_avatar/internals.rust-lang.org/nikomatsakis/32/5410_2.png) [@nikomatsakis](https://internals.rust-lang.org/u/nikomatsakis)\
**Post date:** [April 17, 2017, 10:05am UTC](https://internals.rust-lang.org/t/grammatical-ambiguity-around-catch-blocks/4807/20 "2017-04-17T10:05:24Z")

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Well, it’s a bit late now. =) I’d prefer to solve this permanently with [the concept of epochs](https://internals.rust-lang.org/t/pre-rfc-stable-features-for-breaking-changes/5002/9?u=nikomatsakis), which is exactly the sort of thing we were anticipating when we closed #10293. I think the reason I am not keen on reserving “a bunch of keywords” is that then we wind up picking keywords not based on whether they are the Right Keyword, but based on whether we happen to have reserved it. OTOH, the whole Epoch discussion hasn’t really reached consensus yet, and in particular it’s not clear how often we might want to declare a fresh epoch – if the idea is to do this very rarely, then perhaps it makes sense that, in the next epoch, we reverse course on #10293 and do indeed reserve a bunch of common keywords.

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