Unexport catch_stack

This API is experimental in julia 1.1 and will be replaced with
something more convenient (see #29901). In the meantime, make sure it's
clearly marked as experimental and not exported from Base.

NEWS.md

@@ -4,7 +4,9 @@ Julia v1.1 Release Notes
 New language features
 ---------------------
 
-  * An *exception stack* is maintained on each task to make exception handling more robust and enable root cause analysis using `catch_stack` ([#28878]).
+  * An *exception stack* is maintained on each task to make exception handling
+    more robust and enable root cause analysis. The stack may be accessed using
+    the experimental function `Base.catch_stack` ([#28878]).
   * The experimental macro `Base.@locals` returns a dictionary of current local variable names
     and values ([#29733]).
 

base/error.jl

@@ -105,7 +105,8 @@ arbitrary task. This is useful for inspecting tasks which have failed due to
 uncaught exceptions.
 
 !!! compat "Julia 1.1"
-    This function requires at least Julia 1.1.
+    This function is experimental in Julia 1.1 and will likely be renamed in a
+    future release (see https://github.com/JuliaLang/julia/pull/29901).
 """
 function catch_stack(task=current_task(); include_bt=true)
     raw = ccall(:jl_get_excstack, Any, (Any,Cint,Cint), task, include_bt, typemax(Cint))

base/exports.jl

@@ -682,7 +682,6 @@ export
 # errors
     backtrace,
     catch_backtrace,
-    catch_stack,
     error,
     rethrow,
     retry,

doc/src/manual/control-flow.md

@@ -794,7 +794,7 @@ The power of the `try/catch` construct lies in the ability to unwind a deeply ne
 immediately to a much higher level in the stack of calling functions. There are situations where
 no error has occurred, but the ability to unwind the stack and pass a value to a higher level
 is desirable. Julia provides the [`rethrow`](@ref), [`backtrace`](@ref), [`catch_backtrace`](@ref)
-and [`catch_stack`](@ref) functions for more advanced error handling.
+and [`Base.catch_stack`](@ref) functions for more advanced error handling.
 
 ### `finally` Clauses
 

doc/src/manual/stacktraces.md

@@ -187,7 +187,7 @@ ERROR: Whoops!
 [...]
 ```
 
-## Exception stacks and [`catch_stack`](@ref)
+## Exception stacks and `catch_stack`
 
 !!! compat "Julia 1.1"
     Exception stacks requires at least Julia 1.1.
@@ -197,7 +197,7 @@ identify the root cause of a problem. The julia runtime supports this by pushing
 *exception stack* as it occurs. When the code exits a `catch` normally, any exceptions which were pushed onto the stack
 in the associated `try` are considered to be successfully handled and are removed from the stack.
 
-The stack of current exceptions can be accessed using the [`catch_stack`](@ref) function. For example,
+The stack of current exceptions can be accessed using the experimental [`Base.catch_stack`](@ref) function. For example,
 
 ```julia-repl
 julia> try
@@ -206,7 +206,7 @@ julia> try
            try
                error("(B) An exception while handling the exception")
            catch
-               for (exc, bt) in catch_stack()
+               for (exc, bt) in Base.catch_stack()
                    showerror(stdout, exc, bt)
                    println()
                end

test/exceptions.jl

@@ -1,4 +1,5 @@
 using Test
+using Base: catch_stack
 
 @testset "Basic exception stack handling" begin
     # Exiting the catch block normally pops the exception