address concerns that depwarn for transpose is unclear (JuliaLang#19205)

* close JuliaLang#18320

* Update NEWS.md

* Update deprecated.jl

* Update deprecated.jl

NEWS.md

@@ -508,8 +508,9 @@ Deprecated or removed
  * Sparse matrix functions `etree`, `ereach`, `csc_permute`, and `symperm` have been moved
  to the [SuiteSparse.jl package](https://github.com/JuliaSparse/SuiteSparse.jl) ([#12231], [#17033]).
 
- * The no-op `transpose` fallback has been deprecated. Consider introducing suitable
- `transpose` methods or calling `permutedims(x, [2,1])` ([#13171], [#17075], [#17374]).
+ * The no-op `transpose` fallback for non-numeric arrays has been deprecated. Consider introducing suitable
+ `transpose` methods or calling `permutedims(x, (2, 1))` for matrices and `reshape(x, 1, length(x))` for
+ vectors. ([#13171], [#17075], [#17374]).
 
  * The following macros have been deprecated ([#16219]):
  * `@windows` is deprecated in favor of `is_windows()`

base/deprecated.jl

@@ -765,9 +765,10 @@ end
 
 # Deprecate no-op transpose fallback. Please see #13171 and #17075.
 function transpose(x)
- depwarn(string("the no-op `transpose` fallback is deprecated, and no more specific ",
- "`transpose` method for $(typeof(x)) exists. Consider `permutedims(x, [2, 1])` ",
- "or writing a specific `transpose(x::$(typeof(x)))` method if appropriate."),
+ depwarn(string("the no-op `transpose` for non-numeric arrays is deprecated, ",
+ "and no specific `transpose` method for $(typeof(x)) exists. Use ",
+ "`permutedims(x, (2, 1))` for matrices and `reshape(x, 1, length(x))` for vectors, ",
+ "or write a specific `transpose(x::$(typeof(x)))` method if appropriate."),
  :transpose)
  return x
 end