This commit amends package errors' documentation to include a reference
to the https://go.dev/blog/go1.13-errors blog article. The motivation
is multi-fold, but chiefly the article includes good information about
error philosophy (e.g., when to wrap), and developers who have come to
Go in the intervening five years are likely not have seen this article
at all given the nature of blog publishing and post fanfare. The
material deserves a promotion in visibility.
Change-Id: Ia6f8307784521dd59de3a3d638dbc0a7fcd445e6
GitHub-Last-Rev: 20980dd507
GitHub-Pull-Request: golang/go#69698
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Reviewed-by: Damien Neil <dneil@google.com>
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Change-Id: Ibf28c4b3026019427a2485230e14929ed80a1727
Reviewed-on: https://go-review.googlesource.com/c/go/+/587255
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If err is nil it wouldn't match any given target error except for nil,
so we can return early to speed up cases where Is is used without a
preceding err != nil check.
Change-Id: Ib33cff50453fe070f06871ce8074694c81ab787b
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CL 535080 incorrectly links the unclear mention of Unwrap to the func
Unwrap in doc for errors.Is and errors.As
Instead we clarify that "Unwrap" is a reference
to the "Unwrap() error" or "Unwrap() []error" methods, not to the
"Unwrap(error) error" function which is also available in the package.
Change-Id: I8314993932e1e7a2dc77400f74d81f3a8aa891de
Reviewed-on: https://go-review.googlesource.com/c/go/+/538155
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Change-Id: Iaa1751c6ac0df9d5b2cb74efb16996f4eaea0503
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Handle the case of one error at the beginning.
Use unsafe.String to avoid memory allocation when converting byte slice to string.
Change-Id: Ib23576f72b1d87489e6f17762be483f62ca4998a
GitHub-Last-Rev: ed8003bfbc
GitHub-Pull-Request: golang/go#60026
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Change-Id: I766e656e6b967290d692313ea1391878fc21c92d
Reviewed-on: https://go-review.googlesource.com/c/go/+/497375
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Document that errors returned by Join always implement Unwrap []error.
Explicitly state that Unwrap does not unwrap errors
with an Unwrap() []error method.
Change-Id: Id610345dcf43ca54a9dde157e56c5815c5112073
GitHub-Last-Rev: 7a0ec450bd
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The previous documentation used a double-negative in describing Join behavior; this use of language could be confusing.
This update removes the double-negative.
Change-Id: If13e88682e865314a556e7d381143a97fa5486d9
GitHub-Last-Rev: 92b3f88a5d
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Fixes#41198
Change-Id: Ib33a11d0eb311f8e2b81de24d11df49e00b2fc81
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Change-Id: Ide70476698d82a51881802dd6bf05dd7abcd60e8
GitHub-Last-Rev: ddb251ded6
GitHub-Pull-Request: golang/go#57931
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Change-Id: I77c61211a488c66f1d445c0bf01e35aaf4f83565
GitHub-Last-Rev: c411a56a3b
GitHub-Pull-Request: golang/go#56279
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An error which implements an "Unwrap() []error" method wraps all the
non-nil errors in the returned []error.
We replace the concept of the "error chain" inspected by errors.Is
and errors.As with the "error tree". Is and As perform a pre-order,
depth-first traversal of an error's tree. As returns the first
matching result, if any.
The new errors.Join function returns an error wrapping a list of errors.
The fmt.Errorf function now supports multiple instances of the %w verb.
For #53435.
Change-Id: Ib7402e70b68e28af8f201d2b66bd8e87ccfb5283
Reviewed-on: https://go-review.googlesource.com/c/go/+/432898
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Reviewed-by: Rob Pike <r@golang.org>
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Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
And then revert the bootstrap cmd directories and certain testdata.
And adjust tests as needed.
Not reverting the changes in std that are bootstrapped,
because some of those changes would appear in API docs,
and we want to use any consistently.
Instead, rewrite 'any' to 'interface{}' in cmd/dist for those directories
when preparing the bootstrap copy.
A few files changed as a result of running gofmt -w
not because of interface{} -> any but because they
hadn't been updated for the new //go:build lines.
Fixes#49884.
Change-Id: Ie8045cba995f65bd79c694ec77a1b3d1fe01bb09
Reviewed-on: https://go-review.googlesource.com/c/go/+/368254
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Change-Id: Id2336a6059f7a8d627e6c0661a4d4c05485b65f3
Reviewed-on: https://go-review.googlesource.com/c/go/+/355589
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"so" didn't have an antecedent.
Change-Id: I27f7b334decea7bc34bfa3f3f2d3a79874c6fe90
Reviewed-on: https://go-review.googlesource.com/c/go/+/360797
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
errors.Is internally unwraps the error until the error matches the
target. Because of this, a user-authored Is method on an error type
need not call errors.Unwrap on itself or the target, because that would
make the unwrapping operation O(N^2). It is a subtle detail to remind
authors for resource efficiency reasons.
Change-Id: Ic1ba59a5bdbfe2c7cb51a2cba2537ab6de4a13ff
Reviewed-on: https://go-review.googlesource.com/c/go/+/356789
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The old os references are still valid, but update our code
to reflect best practices and get used to the new locations.
Code compiled with the bootstrap toolchain
(cmd/asm, cmd/dist, cmd/compile, debug/elf)
must remain Go 1.4-compatible and is excluded.
For #41190.
Change-Id: I8f9526977867c10a221e2f392f78d7dec073f1bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/243907
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You can't call Unwrap on the return value of fmt.Errorf, but
you can pass the result to errors.Unwrap.
Also, move the description of the Unwrap function up so the
example makes sense.
Fixes#34061.
Change-Id: Ica07c44665c5e65deea4aa6a146fc543a5a0a99d
Reviewed-on: https://go-review.googlesource.com/c/go/+/193298
Run-TryBot: Jonathan Amsterdam <jba@google.com>
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Add brief descriptions of why one might implement
an Is or As method.
Fixes#33364.
Change-Id: I81a091bf564c654ddb9ef3997e780451a01efb7a
Reviewed-on: https://go-review.googlesource.com/c/go/+/191338
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This reverts commit 739123c3a3.
Reason for revert: broke Windows and Plan 9 builders
Fixes#33828
Change-Id: I1d85c81549b1b34924fdd0ade8bf9406e5cf6555
Reviewed-on: https://go-review.googlesource.com/c/go/+/191742
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Explain wrapping and how to use Is and As in the package doc.
Explain "chain" in Is and As.
Updates #33364.
Change-Id: Ic06362106dbd129e33dd47e63176ee5355492086
Reviewed-on: https://go-review.googlesource.com/c/go/+/188737
Reviewed-by: Rob Pike <r@golang.org>
Check the value of target after As returns true.
Change-Id: I76a2b25fe825ee1dbb5f39f8f0b211c55bd25a4f
Reviewed-on: https://go-review.googlesource.com/c/go/+/181299
Reviewed-by: Bryan C. Mills <bcmills@google.com>
The example in example_test.go requires that the whole file be
displayed; the addition of ExampleAs meant that only the body of the
package example function was shown, rather than the surrounding context.
This change moves ExampleAs to the file wrap_test.go file, restoring the
package example to its former glory.
Update #31716
Change-Id: Id0ea77bc06023b239a63c1d6a7c8b3c1dae91ce9
Reviewed-on: https://go-review.googlesource.com/c/go/+/179737
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The Wrapper type no longer exists.
Change-Id: I21051f26c6722a957295819f2f385f2bbd0db355
Reviewed-on: https://go-review.googlesource.com/c/go/+/177618
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The current example illustrates using As when the error is able to be
interpreted as an os.PathError, but elides the "else" case. This CL adds the
small extra else case to make it clear that it's not safe to assume As will
return true.
This CL also squash the err instantiation and the err nil check into one line
for brevity.
Change-Id: I3d3ab483ffb38fb2788d0498b3f03229a87dd7c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/177717
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golang.org/cl/175260 fixed Is panics if target is uncomparable. It did
add an useless condition checking whether target is comparable. Just
remove that condition.
Change-Id: I0a317056479638d209b0a0cbc7010c153558c087
Reviewed-on: https://go-review.googlesource.com/c/go/+/176497
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Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
The Unwrap function performs a type assertion looking for the Wrapper
interface. The method of that interface is called Unwrap but the
interface itself is called Wrapper.
Change-Id: Ie3bf296f93b773d36015bcab2a0e6585d39783c7
GitHub-Last-Rev: 32b1a0c2f8
GitHub-Pull-Request: golang/go#31794
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This applies only for cases where %w is not used.
The purpose of this change is to reduce test failures where tests
depend on these two being the same type, as they previously were.
Change-Id: I2dd28b93fe1d59f3cfbb4eb0875d1fb8ee699746
Reviewed-on: https://go-review.googlesource.com/c/go/+/167402
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See Issue #29382 and Issue #30468.
Improvements in this CL:
name old time/op new time/op delta
New-8 352ns ± 2% 225ns ± 5% -36.04% (p=0.008 n=5+5)
Improvements together with moving to 1 uintptr:
name old time/op new time/op delta
New-8 475ns ± 3% 225ns ± 5% -52.59% (p=0.008 n=5+5)
Change-Id: I9d69a14e5e10a6498767defb7d5f26ceedcf9ba5
Reviewed-on: https://go-review.googlesource.com/c/go/+/167401
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Unwrap, Is and As are as defined in proposal
Issue #29934.
Also add Opaque for enforcing an error cannot
be unwrapped.
Change-Id: I4f3feaa42e3ee7477b588164ac622ba4d5e77cad
Reviewed-on: https://go-review.googlesource.com/c/163558
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errors.New now implements Formatter and includes Frame
information that is reported when detail is requested.
Partly implements proposal Issue #29934.
Change-Id: Id76888d246d7d862595b5e92d517b9c03f23a7a6
Reviewed-on: https://go-review.googlesource.com/c/163557
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This is a subset of https://golang.org/cl/20022 with only the copyright
header lines, so the next CL will be smaller and more reviewable.
Go policy has been single space after periods in comments for some time.
The copyright header template at:
https://golang.org/doc/contribute.html#copyright
also uses a single space.
Make them all consistent.
Change-Id: Icc26c6b8495c3820da6b171ca96a74701b4a01b0
Reviewed-on: https://go-review.googlesource.com/20111
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