I should have phrased my question as, Has anyone used negative level
besides _1?
L:_1 always means 'open one boxing level' in either definition and
differs from &.> only in that an open argument is passed unchanged to
the opened boxes of the other. To get that effect with the new
definition you would use a level of 0 for the open argument: L:0 _1.
L:_2 in the new definition operates two levels down, akin to &.>&.> .
What it does in the old definition defies simple description.
Henry Rich
On 7/28/2018 7:11 PM, Jose Mario Quintana wrote:
I have, at least, produced code which includes L:_1 in a context in which
it is not equivalent to &.>.
Have you considered to get what you want without potentially breaking
existing code (e.g., giving meaning to imaginary whole numbers for the
right argument of L:)?
(It seems that you wrote L" instead of L: a couple of times in the
description of your proposal.)
On Fri, Jul 27, 2018 at 3:29 PM, Henry Rich <[email protected]> wrote:
I think negative level is wrongly defined. (u L:(-r) y) applies u at
level ((L. y) -r), which measures from the bottom of the tree. What I want
is a form that applies u two levels down, say, which I can't get now. I
propose to change L: to do what I want.
Has anyone found a use for L:(-r) using the current definition?
My proposed change is described at https://code.jsoftware.com/wik
i/System/Interpreter/Requests#Change_definition_of_negative_
level_.28strawman.29
Henry Rich
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