refactor: prepare for boolean functions

* Defines a BooleanT type
  * adds options to the Type constructor, so far just to allow conversions
    from other types
  * renames Number type to NumberT
  * records the name of types, and puts the name in the string representation
  * defines a conversion fron BooleanT to NumberT, specified to be automatic
  * stub code for automatic conversions, not yet complete
  * BooleanT not yet added to nanomath

Checked that the new facilities do not disrupt the prior behavior on numbers.

src/number/Number.js

@@ -1,3 +0,0 @@
-import {Type} from '#core/Type.js'
-
-export const Number = new Type(n => typeof n === 'number')

src/number/NumberT.js

@@ -0,0 +1,6 @@
+import {Type} from '#core/Type.js'
+import {BooleanT} from '#boolean/BooleanT.js'
+
+export const NumberT = new Type(n => typeof n === 'number', {
+    from: [BooleanT]
+})

src/number/__test__/Number.spec.js

@@ -1,11 +0,0 @@
-import assert from 'assert'
-import {Number} from '../Number.js'
-
-describe('Number Type', () => {
-   it('correctly recognizes numbers', () => {
-      assert(Number.test(3))
-      assert(Number.test(NaN))
-      assert(Number.test(Infinity))
-      assert(!Number.test("3"))
-   })
-})

src/number/__test__/NumberT.spec.js

@@ -0,0 +1,11 @@
+import assert from 'assert'
+import {NumberT} from '../NumberT.js'
+
+describe('NumberT Type', () => {
+   it('correctly recognizes numbers', () => {
+      assert(NumberT.test(3))
+      assert(NumberT.test(NaN))
+      assert(NumberT.test(Infinity))
+      assert(!NumberT.test("3"))
+   })
+})

src/number/all.js

@@ -1,4 +1,4 @@
-export * as typeDefinition from './Number.js'
+export * as typeDefinition from './NumberT.js'
 export * as arithmetic from './arithmetic.js'
 export * as type from './type.js'
 export * as utils from './utils.js'

src/number/helpers.js

@@ -1,7 +1,7 @@
-import {Number} from './Number.js'
+import {NumberT} from './NumberT.js'
 
 import {onType} from '#core/helpers.js'
 import {Returns} from '#core/Type.js'
 
 export const plain = f => onType(
-   Array(f.length).fill(Number), Returns(Number, f))
+   Array(f.length).fill(NumberT), Returns(NumberT, f))

src/number/type.js

@@ -1,4 +1,7 @@
 import {plain} from './helpers.js'
+import {BooleanT} from '#boolean/BooleanT.js'
+import {Returns} from '#core/Type.js'
+import {NumberT} from '#number/NumberT.js'
 
-// Not much to do so far when there is only one type
 export const number = plain(a => a)
+number.also(BooleanT, Returns(NumberT, a => a ? 1 : 0))