Command-line completion for lambdas

[Lifepillar]

It seems that there is no way to complete lambdas on the command-line
(or I can't find a way). For instance, these all work (assuming that
<lambda>56 exists):

:fun <lambda>56
:def <lambda>56
:disassemble <lambda>56

But in no case does Tab help me to complete the name of the lambda. It
would be nice if completion worked for lambdas. Wdyt?

Life.