Strange code in layout.js

[dev-tim]

Hi! What does this code mean in tryToFitTile in layout.js file ?

function tryToFitTile(tile) {
        return function (tileSelection) {
            if (tileSelection.some(placedTile)) {
                return false;
            } else {
                                //this one does nothing.
                tileSelection.map(function () {
                    return tile;
                });
                               // ends here
                tile.position = { x: tileSelection.col.start, y: tileSelection.row.start };
                return true;
            }
        };
    }

[mr-mig]

This is a curried function, which have the tryToFix(tile, tileSelection) signature.

The first parameter is the tile which will be attempted to fit, the second parameter is the virtual selection, covering the area where the tile will be attempted.

some method checks whether the real space in matrix, denoted by virtual selection, is occupied already.

If it is not occupied, then the virtual selection is map-ed to the function, returning the tile. This action is actually map the virtual selection to real space inside the matrix, filling it with the tile data.