<Up>/<Down> arrow for navigating command history in debug mode between sessions

[filchristou]

Currently the<Up>/<Down> arrow key can navigate throughout debug history commands but only for the current debug session.
It would be nice if the debug history commands of previous @enter ... calls were available.

Example

Let's say I define the function

function meaninglessfunc(a::T,b::T) where T
    c = zero(T)
    if a > b
        c += max(a,b)
    else
        c += min(a,b)
    end
    return c
end

And I want to debug it:

julia> @enter meaninglessfunc(5,1)
In meaninglessfunc(a, b) at /u/home/wima/fchrstou/code/julia/temp/temp.jl:15
 15  function meaninglessfunc(a::T,b::T) where T
>16      c = zero(T)
 17      if a > b

About to run: (zero)(Int64)
1|debug> bp add max
[ Info: added breakpoint for function max
1] mylittlefunc:22
2] maximum
3] max

1|debug> c
Hit breakpoint:
In max(x, y) at promotion.jl:488
>488  max(x::T, y::T) where {T<:Real} = ifelse(y < x, x, y)

About to run: (<)(1, 5)
1|debug> c
5

Next time I run a debugger, it will not remember any command history

julia> @enter meaninglessfunc(5,1)
In meaninglessfunc(a, b) at /u/home/wima/fchrstou/code/julia/temp/temp.jl:15
 15  function meaninglessfunc(a::T,b::T) where T
>16      c = zero(T)
 17      if a > b

About to run: (zero)(Int64)
1|debug> <Up-Arrow> # nothing happens

When I add a series of peculiar breakpoint to different functions and files, it would be nice that I can easily carry on this setup in consecutive debugging sessions, rather than painfully redefining them.