nanomath/src/generic/arithmetic.js

import {iterateBinary, ReturnsAs} from './helpers.js'
import {plain} from "#number/helpers.js"

import {Returns, ReturnType, ReturnTyping} from '#core/Type.js'
import {match, Any} from '#core/TypePatterns.js'

export const norm = match(Any, (math, T) => {
   const normsq = math.normsq.resolve(T)
   const sqrt = math.sqrt.resolve(
      ReturnType(normsq), ReturnTyping.conservative)
   return ReturnsAs(sqrt, t => sqrt(normsq(t)))
})

export const abs = norm // coincide for most types (scalars)

export const conj = match(Any, (_math, T) => Returns(T, t => t))

export const square = match(Any, (math, T, strategy) => {
   const mult = math.multiply.resolve([T, T], strategy)
   return ReturnsAs(mult, t => mult(t, t))
})

export const add = iterateBinary('add')
add.push(plain(() => 0))

export const multiply = iterateBinary('multiply')
multiply.push(plain(() => 1))