Press v to toggle showing the value of the current field.

[NHDaly]

Press v to toggle showing the value of the current field.

We retrieve the first line of show(eval(field_path)), terminating the Task after it's printed one line, so it doesn't hang if you try to print a very large object.

To achieve that termination, this PR also defines a small helper utility, WriteBlockingIO <: IO which blocks a task on printing each character, and throws an exception to that task when you close the IO.

Example:

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Select a field to recurse into or ↩ to ascend. [q]uit.

Commands: [J]ump to field path.  Toggle [V]alue.
Toggles: [v]alue of the current field.

(d.vals[7])::Tuple{Int64,Int64} => 16.0 B
0 Allocated Indexes:
 → ↩

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Select a field to recurse into or ↩ to ascend. [q]uit.

Commands: [J]ump to field path.  Toggle [V]alue.
Toggles: [v]alue of the current field.

(2, 3) => 16.0 B
0 Allocated Indexes:
 → ↩