initial checkin

Signed-off-by: Dr. Carsten Leue <carsten.leue@de.ibm.com>
2025-06-17 00:07:49 +02:00 · 2023-07-07 22:31:06 +02:00
parent 71c47ca560
commit c07df5c771
128 changed files with 5827 additions and 2 deletions
--- a/function/function.go
+++ b/function/function.go
@ -0,0 +1,218 @@
+package function
+
+// what a mess, golang does not have proper types ...
+
+func Pipe1[A, R any](a A, f1 func(a A) R) R {
+	// return f1(a)
+	r1 := f1(a)
+	return r1
+}
+
+func Pipe2[A, T1, R any](a A, f1 func(a A) T1, f2 func(t1 T1) R) R {
+	// return f2(f1(a))
+	r1 := f1(a)
+	r2 := f2(r1)
+	return r2
+}
+
+func Pipe3[A, T1, T2, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) R) R {
+	// return f3(f2(f1(a)))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	return r3
+}
+
+func Pipe4[A, T1, T2, T3, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) R) R {
+	// return f4(f3(f2(f1(a))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	return r4
+}
+
+func Pipe5[A, T1, T2, T3, T4, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) R) R {
+	// return f5(f4(f3(f2(f1(a)))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	r5 := f5(r4)
+	return r5
+}
+
+func Pipe6[A, T1, T2, T3, T4, T5, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) R) R {
+	// return f6(f5(f4(f3(f2(f1(a))))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	r5 := f5(r4)
+	r6 := f6(r5)
+	return r6
+}
+
+func Pipe7[A, T1, T2, T3, T4, T5, T6, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) R) R {
+	// return f7(f6(f5(f4(f3(f2(f1(a)))))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	r5 := f5(r4)
+	r6 := f6(r5)
+	r7 := f7(r6)
+	return r7
+}
+
+func Pipe8[A, T1, T2, T3, T4, T5, T6, T7, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) T7, f8 func(t7 T7) R) R {
+	// return f8(f7(f6(f5(f4(f3(f2(f1(a))))))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	r5 := f5(r4)
+	r6 := f6(r5)
+	r7 := f7(r6)
+	r8 := f8(r7)
+	return r8
+}
+
+func Pipe9[A, T1, T2, T3, T4, T5, T6, T7, T8, R any](a A, f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) T7, f8 func(t7 T7) T8, f9 func(t8 T8) R) R {
+	// return f9(f8(f7(f6(f5(f4(f3(f2(f1(a)))))))))
+	r1 := f1(a)
+	r2 := f2(r1)
+	r3 := f3(r2)
+	r4 := f4(r3)
+	r5 := f5(r4)
+	r6 := f6(r5)
+	r7 := f7(r6)
+	r8 := f8(r7)
+	r9 := f9(r8)
+	return r9
+}
+
+func Flow1[A, R any](f1 func(a A) R) func(a A) R {
+	return f1
+}
+
+func Flow2[A, T1, R any](f1 func(a A) T1, f2 func(t1 T1) R) func(a A) R {
+	return func(a A) R {
+		return Pipe2(a, f1, f2)
+	}
+}
+
+func Flow3[A, T1, T2, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) R) func(a A) R {
+	return func(a A) R {
+		return Pipe3(a, f1, f2, f3)
+	}
+}
+
+func Flow4[A, T1, T2, T3, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) R) func(a A) R {
+	return func(a A) R {
+		return Pipe4(a, f1, f2, f3, f4)
+	}
+}
+
+func Flow5[A, T1, T2, T3, T4, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) R) func(a A) R {
+	return func(a A) R {
+		return Pipe5(a, f1, f2, f3, f4, f5)
+	}
+}
+
+func Flow6[A, T1, T2, T3, T4, T5, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) R) func(a A) R {
+	return func(a A) R {
+		return Pipe6(a, f1, f2, f3, f4, f5, f6)
+	}
+}
+
+func Flow7[A, T1, T2, T3, T4, T5, T6, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) R) func(a A) R {
+	return func(a A) R {
+		return Pipe7(a, f1, f2, f3, f4, f5, f6, f7)
+	}
+}
+
+func Flow8[A, T1, T2, T3, T4, T5, T6, T7, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) T7, f8 func(t7 T7) R) func(a A) R {
+	return func(a A) R {
+		return Pipe8(a, f1, f2, f3, f4, f5, f6, f7, f8)
+	}
+}
+
+func Flow9[A, T1, T2, T3, T4, T5, T6, T7, T8, R any](f1 func(a A) T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) T4, f5 func(t4 T4) T5, f6 func(t5 T5) T6, f7 func(t6 T6) T7, f8 func(t7 T7) T8, f9 func(t8 T8) R) func(a A) R {
+	return func(a A) R {
+		return Pipe9(a, f1, f2, f3, f4, f5, f6, f7, f8, f9)
+	}
+}
+
+// Identity returns the value 'a'
+func Identity[A any](a A) A {
+	return a
+}
+
+// Constant creates a nullary function that returns the constant value 'a'
+func Constant[A any](a A) func() A {
+	return func() A {
+		return a
+	}
+}
+
+// Constant1 creates a unary function that returns the constant value 'a' and ignores its input
+func Constant1[B, A any](a A) func(B) A {
+	return func(_ B) A {
+		return a
+	}
+}
+
+// Constant2 creates a binary function that returns the constant value 'a' and ignores its inputs
+func Constant2[B, C, A any](a A) func(B, C) A {
+	return func(_ B, _ C) A {
+		return a
+	}
+}
+
+func IsNil[A any](a *A) bool {
+	return a == nil
+}
+
+func IsNonNil[A any](a *A) bool {
+	return a != nil
+}
+
+// Swap returns a new binary function that changes the order of input parameters
+func Swap[T1, T2, R any](f func(T1, T2) R) func(T2, T1) R {
+	return func(t2 T2, t1 T1) R {
+		return f(t1, t2)
+	}
+}
+
+// First returns the first out of two input values
+func First[T1, T2 any](t1 T1, _ T2) T1 {
+	return t1
+}
+
+// Second returns the second out of two input values
+func Second[T1, T2 any](_ T1, t2 T2) T2 {
+	return t2
+}
+
+func Nullary1[R any](f1 func() R) func() R {
+	return f1
+}
+
+func Nullary2[T1, R any](f1 func() T1, f2 func(t1 T1) R) func() R {
+	return func() R {
+		return Pipe1(f1(), f2)
+	}
+}
+
+func Nullary3[T1, T2, R any](f1 func() T1, f2 func(t1 T1) T2, f3 func(t2 T2) R) func() R {
+	return func() R {
+		return Pipe2(f1(), f2, f3)
+	}
+}
+
+func Nullary4[T1, T2, T3, R any](f1 func() T1, f2 func(t1 T1) T2, f3 func(t2 T2) T3, f4 func(t3 T3) R) func() R {
+	return func() R {
+		return Pipe3(f1(), f2, f3, f4)
+	}
+}