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| author | Who? Me?! <mark-i-m@users.noreply.github.com> | 2018-10-22 12:37:13 -0500 |
|---|---|---|
| committer | Who? Me?! <mark-i-m@users.noreply.github.com> | 2018-10-31 20:44:30 -0500 |
| commit | 5c7a3cf289b9ecc50cfe0ec58fd1b92baf13877d (patch) | |
| tree | 396bbb70baba4efbe9d5cc59af782b7828ee44db /src/doc/rustc-dev-guide | |
| parent | 6ff0b470bc380300f101b5266e832d82b6e0845a (diff) | |
| download | rust-5c7a3cf289b9ecc50cfe0ec58fd1b92baf13877d.tar.gz rust-5c7a3cf289b9ecc50cfe0ec58fd1b92baf13877d.zip | |
Clarify why 'static is free
Diffstat (limited to 'src/doc/rustc-dev-guide')
| -rw-r--r-- | src/doc/rustc-dev-guide/src/traits/canonicalization.md | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/src/doc/rustc-dev-guide/src/traits/canonicalization.md b/src/doc/rustc-dev-guide/src/traits/canonicalization.md index 62c4d9f7483..ca81d6fd166 100644 --- a/src/doc/rustc-dev-guide/src/traits/canonicalization.md +++ b/src/doc/rustc-dev-guide/src/traits/canonicalization.md @@ -42,7 +42,11 @@ This query contains two unbound variables, but it also contains the lifetime `'static`. The trait system generally ignores all lifetimes and treats them equally, so when canonicalizing, we will *also* replace any [free lifetime](../appendix/background.html#free-vs-bound) with a -canonical variable. Therefore, we get the following result: +canonical variable (Note that `'static` is actually a _free_ lifetime +variable here. We are not considering it in the typing context of the whole +program but only in the context of this trait reference. Mathematically, we +are not quantifying over the whole program, but only this obligation). +Therefore, we get the following result: ```text ?0: Foo<'?1, ?2> |