Data commit

Task/Test-integerness/Pascal/test-integerness.pas

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+program integerness(output);
+
+{ determines whether a `complex` also fits in `integer` ---------------- }
+function isRealIntegral(protected x: complex): Boolean;
+begin
+	{ It constitutes an error if no value for `trunc(x)` exists, }
+	{ thus check re(x) is in the range -maxInt..maxInt first. }
+	isRealIntegral := (im(x) = 0.0) and_then
+		(abs(re(x)) <= maxInt * 1.0) and_then
+		(trunc(re(x)) * 1.0 = re(x))
+end;
+
+{ calls isRealIntegral with zero imaginary part ------------------------ }
+function isIntegral(protected x: real): Boolean;
+begin
+	isIntegral := isRealIntegral(cmplx(x * 1.0, 0.0))
+end;
+
+{ Rosetta code test ---------------------------------------------------- }
+procedure test(protected x: complex);
+begin
+	writeLn(re(x), ' + ', im(x), ' 𝒾 : ',
+		isIntegral(re(x)), ' ', isRealIntegral(x))
+end;
+	
+{ === MAIN ============================================================= }
+begin
+	test(cmplx(25.0, 0.0));
+	test(cmplx(24.999999, 0.0));
+	test(cmplx(25.000100, 0.0));
+	test(cmplx(-2.1E120, 0.0));
+	test(cmplx(-5E-2, 0.0));
+	test(cmplx(5.0, 0.0));
+	test(cmplx(5, -5));
+end.