✨ feat(IntegerRing): Add .has() method.

Author: make-github-pseudonymous-again

src/IntegerRing.js

@@ -99,4 +99,9 @@ export class IntegerRing {
 		return new Integer( this.base , -1 , [ 1 ] ) ;
 	}
 
+	has ( x ) {
+		if ( x instanceof Integer ) return true ;
+		return Number.isInteger(x) ;
+	}
+
 }

test/src/ZZ/has.js

@@ -0,0 +1,37 @@
+import test from 'ava' ;
+
+import { ZZ } from '../../../src' ;
+
+const has = ( t , x ) => t.true( ZZ.has(x) ) ;
+has.title = ( providedTitle , x ) => `ZZ contains ${x.toString()}.`
+
+const hasnot = ( t , x ) => t.false( ZZ.has(x) ) ;
+hasnot.title = ( providedTitle , x ) => `ZZ does not contain ${JSON.stringify(x)}.`
+
+test( has , -1 ) ;
+test( has , 0 ) ;
+test( has , 1 ) ;
+
+test( has , ZZ.from(-1234) ) ;
+
+test( has , ZZ.from('98213037479498473209740509327409327492744596398574') ) ;
+test( has , ZZ.from('-98213037479849847320974050937409327492744596398574') ) ;
+
+test( has , ZZ.from('3b', 16) ) ;
+
+test( hasnot , '98213037479498473209740509327409327492744596398574' ) ;
+test( hasnot , '-98213037479849847320974050937409327492744596398574' ) ;
+
+test( hasnot , '0' ) ;
+test( hasnot , 'ff' ) ;
+test( hasnot , 'fdsalkjflsakjfd' ) ;
+
+test( hasnot , [] ) ;
+test( hasnot , {} ) ;
+test( hasnot , '' ) ;
+test( hasnot , false ) ;
+test( hasnot , true ) ;
+test( hasnot , 0.1 ) ;
+test( hasnot , -0.5 ) ;
+test( hasnot , Math.PI ) ;
+test( hasnot , Math.E ) ;