don't mutate lhs while destructuring #40737
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
simeonschaub
added
compiler:lowering
|
Triage thinks this is the right thing to do. |
simeonschaub
force-pushed
the
sds/destructure_aliasing
branch
from
4d07e2f to
bcccabf
Compare
simeonschaub
added a commit
that referenced
this pull request
May 6, 2021
Discovered while working on #40737. Currently, this throws an unintuitive error: ```julia julia> a, f()... = 1, 2, 3 ERROR: syntax: ssavalue with no def Stacktrace: [1] top-level scope @ REPL[1]:1 ``` Might as well fix this properly - Why not allow function definitions to slurp a little from time to time? ;)
|
@nanosoldier |
simeonschaub
changed the title
simeonschaub
removed
needs news
|
Your package evaluation job has completed - possible new issues were detected. A full report can be found here. cc @maleadt |
|
@nanosoldier |
|
Your package evaluation job has completed - possible new issues were detected. A full report can be found here. cc @maleadt |
|
This does seem strictly better. I'm pretty sure we can sweep any breakage under the rug of undefined behavior. |
StefanKarpinski
added
the
minor change
simeonschaub
force-pushed
the
sds/destructure_aliasing
branch
from
dbe795d to
560dcc7
Compare
Jeff was a bit sceptical about this in #40574, but I think this is worth doing since it seems strictly more useful than the current behavior and we already go out of our way in cases like `x, y = y, x` to only assign to the lhs after the rhs has been evaluated, so I think handling `x[2], x[1] = x` in a similar way would only be consistent. As a general rule that assignment will always happen after destructuring does not seem much less obvious than the current behavior to me. This might technically be slightly breaking, but I would be surprised if people relied on the current behavior here. Nevertheless, it would probably be good to run PkgEval if we decide to go with this change. closes #40574
simeonschaub
force-pushed
the
sds/destructure_aliasing
branch
from
560dcc7 to
030bf53
Compare
simeonschaub
removed
the
merge me
shirodkara
pushed a commit
to shirodkara/julia
that referenced
this pull request
Jun 9, 2021
Jeff was a bit sceptical about this in JuliaLang#40574, but I think this is worth doing since it seems strictly more useful than the current behavior and we already go out of our way in cases like `x, y = y, x` to only assign to the lhs after the rhs has been evaluated, so I think handling `x[2], x[1] = x` in a similar way would only be consistent. As a general rule that assignment will always happen after destructuring does not seem much less obvious than the current behavior to me. This might technically be slightly breaking, but I would be surprised if people relied on the current behavior here. Nevertheless, it would probably be good to run PkgEval if we decide to go with this change. closes JuliaLang#40574
simeonschaub
added a commit
that referenced
this pull request
Jul 2, 2021
Discovered while working on #40737. Currently, this throws an unintuitive error: ```julia julia> a, f()... = 1, 2, 3 ERROR: syntax: ssavalue with no def Stacktrace: [1] top-level scope @ REPL[1]:1 ``` Might as well fix this properly - Why not allow function definitions to slurp a little from time to time? ;)
johanmon
pushed a commit
to johanmon/julia
that referenced
this pull request
Jul 5, 2021
Jeff was a bit sceptical about this in JuliaLang#40574, but I think this is worth doing since it seems strictly more useful than the current behavior and we already go out of our way in cases like `x, y = y, x` to only assign to the lhs after the rhs has been evaluated, so I think handling `x[2], x[1] = x` in a similar way would only be consistent. As a general rule that assignment will always happen after destructuring does not seem much less obvious than the current behavior to me. This might technically be slightly breaking, but I would be surprised if people relied on the current behavior here. Nevertheless, it would probably be good to run PkgEval if we decide to go with this change. closes JuliaLang#40574
johanmon
pushed a commit
to johanmon/julia
that referenced
this pull request
Jul 5, 2021
Discovered while working on JuliaLang#40737. Currently, this throws an unintuitive error: ```julia julia> a, f()... = 1, 2, 3 ERROR: syntax: ssavalue with no def Stacktrace: [1] top-level scope @ REPL[1]:1 ``` Might as well fix this properly - Why not allow function definitions to slurp a little from time to time? ;)
KristofferC
pushed a commit
that referenced
this pull request
Jul 7, 2021
Discovered while working on #40737. Currently, this throws an unintuitive error: ```julia julia> a, f()... = 1, 2, 3 ERROR: syntax: ssavalue with no def Stacktrace: [1] top-level scope @ REPL[1]:1 ``` Might as well fix this properly - Why not allow function definitions to slurp a little from time to time? ;) (cherry picked from commit 5c49a0d)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
@JeffBezanson was a bit sceptical about this in #40574, but I think this
is worth doing since it seems strictly more useful than the current
behavior and we already go out of our way in cases like
x, y = y, xtoonly assign to the lhs after the rhs has been evaluated, so I think
handling
x[2], x[1] = xin a similar way would only be consisten. As ageneral rule that assignment will always happen after destructuring does
not seem much less obvious than the current behavior to me. This might
technically be slightly breaking, but I would be surprised if people
relied on the current behavior here. Nevertheless, it would probably
good to run PkgEval if we decide to go with this change.
closes #40574