The Diagonal Suite: Gentle thunking goes a long way!

It looks like there's a bit more room for some gentle thunking to reduce calculation times even more.

For example, with Traverseλ 'result' is deferred until the very end.  I snuck the () in at the end so it's not needed at the sheet level.

// --- Workbook module ---
// A file of name definitions of the form:
//    name = definition;

//Author:   Patrick H.
//Date:     10/27/2025
//Version:  1.0
//Repo:     Please see The Diagonal Suite for a full suite of functions.

//-------------------------------------------------------------------------------------------
//Traverseλ -   Directional Axis Remapper
//-------------------------------------------------------------------------------------------

//The selected axis is remapped to the top-left traversal order.

//Accepted directions:
//  "NE" or 1 → Northeast (↗)
//  "SE" or 2 → Southeast (↘)
//  "SW" or 3 → Southwest (↙)

//Parameters:
//array     →   2D input array (scalars not accepted)
//new_axis  →   Axis direction ("NE", "SE", "SW" or 1–3)

Traverseλ =
LAMBDA(
    array,
    new_axis,

//Input validation
IF(OR(ROWS(array)=1,COLUMNS(array)=1),                "#2D-ARRAY!",
IF(AND(ISNUMBER(new_axis),OR(new_axis<=0,new_axis>3)),"#AXIS!",

LET(
    //Dimensions
    i,      ROWS(array),
    j,      COLUMNS(array),

    //Axis traversal indices (deferred)
   
    x_NE,   LAMBDA(SEQUENCE(j,,1,0)*SEQUENCE(,i)),
    y_NE,   LAMBDA(SEQUENCE(j,,j,-1)*SEQUENCE(,i,1,0)),

    x_SE,   LAMBDA(SEQUENCE(i,,i,-1)*SEQUENCE(,j,1,0)),
    y_SE,   LAMBDA(SEQUENCE(i,,j,0)+SEQUENCE(,j,0,-1)),
    

    x_SW,   LAMBDA(SEQUENCE(j,,i,0)+SEQUENCE(,i,0,-1)),
    y_SW,   LAMBDA(SEQUENCE(j,,1)*SEQUENCE(,i,1,0)),

    //Axis mode selection
    mode,   IF(ISNUMBER(new_axis),new_axis,
                              SWITCH(new_axis,"NE",1,"SE",2,"SW",3,1)),
    //Index selection
    x,      CHOOSE(mode,x_NE,x_SE,x_SW),
    y,      CHOOSE(mode,y_NE,y_SE,y_SW),
    
    //Unwrap indices but defer results until function invocation
    result, LAMBDA(INDEX(array,x(),y())),
    result
)
))());

This is fascinating in how a simple LAMBDA() tells Excel's formula parser to not read/fully evaluate a line and to treat it as "unrealized code".

Timings: