Inspection

There are two inspective functions in Cropbox that allow us to look at systems more closely. For information regarding syntax, please check the reference.

look()
dive()

`look()`

The look() provides a convenient way of accessing variables within a system.

Example

"""
This is a system.
"""
@system S begin
    """
    This is a parameter.
    """
    a ~ preserve(parameter)
end

look(S)

[doc]
  This is a system.

[system]
S
  context
  config
  a

look(S, :a)

[doc]
  This is a parameter.

[code]
  a ~ preserve(parameter)

Note

There is a macro version of this function, @look, which allows you to access a variable without using a symbol.

@look S
@look S a
@look S, a

Both @look S.a and @look S a are identical to look(S, :a).

`dive()`

The dive() function allows us to inspect an instance of a system by navigating through the hierarchy of variables displayed in a tree structure.

Pressing up/down arrow keys allows navigation. Press 'enter' to dive into a deeper level and press 'q' to come back. A leaf node of the tree shows an output of look regarding the variable. Pressing 'enter' again would return a variable itself and exit to REPL.

This function only works in a terminal environment and will not work in Jupyter Notebook.

Example

julia> @system S(Controller) begin
           a => 1 ~ preserve(parameter)
       end;
julia> s = instance(S);
julia> dive(s)
S
 → context = <Context>
   config = <Config>
   a = 1.0