As written, the conversion P(x), where P and the type
of x are type parameters with identical underlying types
(i.e., identical constraints), is valid. However, unless
the type of x and P are identical (which is covered with
the assignability rule), such a conversion is not valid
in general (consider the case where both type parameters
are different type parameters with constraint "any").
This change adjusts the rules to prohibit type parameters
in this case. The same reasoning applies and the analogue
change is made for pointer types.
The type checker already implements these updated rules.
Change-Id: Id90187900cb2820f6a0a0cf582cf26cdf8addbce
Reviewed-on: https://go-review.googlesource.com/c/go/+/371074
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
cmd/vet has several precision improvements for the checkers copylock, printf, sortslice, testinggoroutine, and tests. Adds a high level mention in the release notes and an example of string constant concatenation.
Updates #47694
Change-Id: I7a342a57ca3fd9e2f3e8ec99f7b647269798317f
Reviewed-on: https://go-review.googlesource.com/c/go/+/370734
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
Trust: Tim King <taking@google.com>
Run-TryBot: Tim King <taking@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Also update some other go/types release notes to use the present tense.
Updates #47694
Change-Id: I654371c065e76fd5d22679d0d3c1a81bc3d1e513
Reviewed-on: https://go-review.googlesource.com/c/go/+/370235
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
This CL reorders the bullet points in the generics section to more
closely match what I think users will consider most important. I put
the ~ token before the mention of ~T in interfaces to avoid a forward
reference, though I wonder if we actually want to spent a couple more
sentences saying what union and ~T types are, since most people are
going to care about that a lot more than they care about the low-level
detail that there's a new token.
For #47694.
Change-Id: Ib84f096ef6346a711801268ce362b64fa423d3f2
Reviewed-on: https://go-review.googlesource.com/c/go/+/369734
Trust: Austin Clements <austin@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
NewTypeList was not part of the go/types API proposal, and was left in
by accident. It also shouldn't be necessary, so remove it.
Updates #47916
Change-Id: I4db3ccf036ccfb708ecf2c176ea4921fe68089a4
Reviewed-on: https://go-review.googlesource.com/c/go/+/369475
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
For #47694
Change-Id: Iee4fda069a56ea4436b8aa32e2605f3349d7c154
Reviewed-on: https://go-review.googlesource.com/c/go/+/369334
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Also, move it up in the document.
Updates #47694
Change-Id: I927c4c845089a5c22e2c5b5f3de1831c04c6d990
Reviewed-on: https://go-review.googlesource.com/c/go/+/369102
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
The number of involved CLs is too large (hundreds) so
no CLs are mentioned in (html) comments.
Updates #47694
Change-Id: I655d800a1e56a71e9d70a190f1c42c17baf6861e
Reviewed-on: https://go-review.googlesource.com/c/go/+/369099
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
Also make a few small formatting fixes.
Change-Id: Iad99d030312393af3b6533f2cd00f09aea0f2a7d
Reviewed-on: https://go-review.googlesource.com/c/go/+/369074
Trust: Katie Hockman <katie@golang.org>
Run-TryBot: Katie Hockman <katie@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
For #44853
For #47694
Change-Id: Ia76246218b1361d8bdf510bbfc5178c83cdd3eec
Reviewed-on: https://go-review.googlesource.com/c/go/+/368834
Trust: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This is based off Michael's notes.
Updates #47694
Change-Id: I6e7944f85b776e8481829a2fafd177a49557c6ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/368156
Trust: Jeremy Faller <jeremy@golang.org>
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
This description is based on https://golang.org/cl/321490.
Updates #47694
Change-Id: I48656cd487d2fccf0b0d3390f350f1bc6f2b0080
Reviewed-on: https://go-review.googlesource.com/c/go/+/365738
Trust: Jeremy Faller <jeremy@golang.org>
Trust: Dmitri Shuralyov <dmitshur@golang.org>
Run-TryBot: Jeremy Faller <jeremy@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Change-Id: I562d4648756e710020ee491f3801896563a89baa
Reviewed-on: https://go-review.googlesource.com/c/go/+/367395
Trust: Robert Griesemer <gri@golang.org>
Trust: Dan Scales <danscales@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
We want to support some special cases for index expressions, len, and
cap on operands of type parameters (such as indexing a value constrained
by byte slices and strings), hence the extra rules.
Change-Id: I4a07dc7e64bb47361b021d606c52eae1784d5430
Reviewed-on: https://go-review.googlesource.com/c/go/+/366814
Trust: Robert Griesemer <gri@golang.org>
Trust: Dan Scales <danscales@google.com>
Reviewed-by: Dan Scales <danscales@google.com>
- fix definition of "specific types" and add more examples
- state that a parameterized function must be instantiated
when used as a function value
- remove duplicate word ("can can" -> "can")
Thanks to @danscales for finding these.
Change-Id: Ideb41efc35a3e67694d3bc97e462454feae37c44
Reviewed-on: https://go-review.googlesource.com/c/go/+/367394
Trust: Robert Griesemer <gri@golang.org>
Trust: Dan Scales <danscales@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
For #47694.
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Change-Id: I38c2fd9b57fbbacf220a2bc679f67e2dfdcc7cb1
Reviewed-on: https://go-review.googlesource.com/c/go/+/367514
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
This change corrects the link `Instantiantions` to `Instantiations` in the spec.
Change-Id: Ib0ed03420ae401d20af1ea723c5487018b2f462d
GitHub-Last-Rev: b84316c818
GitHub-Pull-Request: golang/go#49816
Reviewed-on: https://go-review.googlesource.com/c/go/+/367274
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Change-Id: I11111b3617673be94508128489aed6488d518537
Reviewed-on: https://go-review.googlesource.com/c/go/+/366834
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>