Map values in array of objects

Question

I have an array

const nodes = [
    { layer: '0' },
    { layer: 'input' },
    { layer: '0' },
    { layer: 'output' },
    { layer: '1' }
};

I want to keep the array, but all the layer values should be changed.

The input layer should have value 1, all the numeric values should be increased by 2 and the output layer should have the new highest numeric value plus 1. All the values should be numbers instead of strings.

So the new array will be

const nodes = [
    { layer: 2 },
    { layer: 1 },
    { layer: 2 },
    { layer: 4 },
    { layer: 3 }
};

I have accomplished this with

const nodes = [
    { layer: '0' },
    { layer: 'input' },
    { layer: '0' },
    { layer: 'output' },
    { layer: '1' }
};

const output = Math.max.apply(Math, nodes.map((node) => Number.parseInt(node.layer, 10) || 0)) + 3;

nodes.map((node) => {
  layer: neuron.layer === 'input' ? 1 : (neuron.layer === 'output' ? output : Number.parseInt(neuron.layer, 10) + 2)
})

It seems to work, but the code is really ugly.

I wonder if it can be done more neat than this.

Answer 1

This might be one way of doing this job;

 var nodes = [ { layer: '0' }, { layer: 'input' }, { layer: '0' }, { layer: 'output' }, { layer: '1' } ], result = nodes.map(n => isNaN(+n.layer) ? n.layer === "input" ? {layer:1} : {layer: n.layer} : n.layer = {layer:+n.layer + 2}); result.find(o => o.layer === "output").layer = result.filter(f => !isNaN(f.layer)) .reduce((p,c) => p.layer > c.layer ? p : c) .layer + 1; console.log(result); 

Answer 2

What about this:

 const nodes = [ { layer: '0' }, { layer: 'input' }, { layer: '0' }, { layer: 'output' }, { layer: '1' } ]; nodes.filter( o => o.layer === 'output' )[0].layer = 1 + nodes.reduce( (max, node) => Math.max(max, node.layer = +(node.layer === 'input') || +node.layer+2 || 0), 0); console.log(nodes); 

For those wondering about const here: the constant nature only protects the variable from a reassignment; but the objects stored within the array can be freely mutated.