buildSrc/src/main/kotlin/kscience/kmath/gsl/codegen/PsiTestUtil.kt

@@ -70,4 +70,4 @@ internal object PsiTestUtil {
         if (dummyCopy is PsiFileImpl) dummyCopy.originalFile = file
         return dummyCopy
     }
-}
+}

buildSrc/src/main/kotlin/kscience/kmath/gsl/codegen/matricesCodegen.kt

@@ -23,33 +23,35 @@ private fun KtPsiFactory.createMatrixClass(
     scope: DeferScope
 ) : GslMatrix<$kotlinTypeName, $structName>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): $className =
-        ${className}(nativeHandle, this.features + features, scope)
+        ${className}(nativeHandleChecked(), this.features + features, scope)
 
     override operator fun get(i: Int, j: Int): $kotlinTypeName = ${
         fn("gsl_matrixRget", cTypeName)
-    }(nativeHandle, i.toULong(), j.toULong())
+    }(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: ${kotlinTypeName}): Unit =
-        ${fn("gsl_matrixRset", cTypeName)}(nativeHandle, i.toULong(), j.toULong(), value)
+        ${fn("gsl_matrixRset", cTypeName)}(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): $className {
         val new = requireNotNull(${fn("gsl_matrixRalloc", cTypeName)}(rowNum.toULong(), colNum.toULong()))
-        ${fn("gsl_matrixRmemcpy", cTypeName)}(new, nativeHandle)
+        ${fn("gsl_matrixRmemcpy", cTypeName)}(new, nativeHandleChecked())
         return $className(new, features, scope)
     }
 
-    override fun close(): Unit = ${fn("gsl_matrixRfree", cTypeName)}(nativeHandle)
+    override fun close(): Unit = ${fn("gsl_matrixRfree", cTypeName)}(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is $className) return ${fn("gsl_matrixRequal", cTypeName)}(nativeHandle, other.nativeHandle) == 1
+        if (other is $className) return ${
+        fn("gsl_matrixRequal", cTypeName)
+    }(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }"""

buildSrc/src/main/kotlin/kscience/kmath/gsl/codegen/vectorsCodegen.kt

@@ -21,25 +21,31 @@ private fun KtPsiFactory.createVectorClass(
         """internal class $className(override val nativeHandle: CPointer<$structName>, scope: DeferScope) : 
     GslVector<$kotlinTypeName, $structName>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): $kotlinTypeName = ${fn("gsl_vectorRget", cTypeName)}(nativeHandle, index.toULong())
+    override fun get(index: Int): $kotlinTypeName = ${
+            fn("gsl_vectorRget",
+                cTypeName)
+        }(nativeHandleChecked(), index.toULong())
     override fun set(index: Int, value: $kotlinTypeName): Unit = ${
             fn("gsl_vectorRset", cTypeName)
-        }(nativeHandle, index.toULong(), value)
+        }(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): $className {
         val new = requireNotNull(${fn("gsl_vectorRalloc", cTypeName)}(size.toULong()))
-        ${fn("gsl_vectorRmemcpy", cTypeName)}(new, nativeHandle)
+        ${fn("gsl_vectorRmemcpy", cTypeName)}(new, nativeHandleChecked())
         return ${className}(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is $className) return ${fn("gsl_vectorRequal", cTypeName)}(nativeHandle, other.nativeHandle) == 1
+        if (other is $className) return ${
+            fn("gsl_vectorRequal",
+                cTypeName)
+        }(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = ${fn("gsl_vectorRfree", cTypeName)}(nativeHandle)
+    override fun close(): Unit = ${fn("gsl_vectorRfree", cTypeName)}(nativeHandleChecked())
 }"""
 
     f += createClass(text)

kmath-gsl/src/nativeMain/kotlin/kscience/kmath/gsl/GslMemoryHolder.kt

@@ -8,14 +8,26 @@ import kotlinx.cinterop.DeferScope
  * Represents managed native GSL object. The only property this class holds is pointer to the GSL object. In order to be
  * freed this class's object must be added to [DeferScope].
  *
+ * The objects of this type shouldn't be used after being disposed by the scope.
+ *
  * @param scope the scope where this object is declared.
  */
 public abstract class GslMemoryHolder<H : CStructVar> internal constructor(internal val scope: DeferScope) {
     internal abstract val nativeHandle: CPointer<H>
+    private var isClosed: Boolean = false
 
     init {
         ensureHasGslErrorHandler()
-        scope.defer(::close)
+
+        scope.defer {
+            close()
+            isClosed = true
+        }
+    }
+
+    internal fun nativeHandleChecked(): CPointer<H> {
+        check(!isClosed) { "The use of GSL object that is closed." }
+        return nativeHandle
     }
 
     internal abstract fun close()

kmath-gsl/src/nativeMain/kotlin/kscience/kmath/gsl/_Matrices.kt

@@ -10,31 +10,31 @@ internal class GslRealMatrix(
     scope: DeferScope
 ) : GslMatrix<Double, gsl_matrix>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslRealMatrix =
-        GslRealMatrix(nativeHandle, this.features + features, scope)
+        GslRealMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): Double = gsl_matrix_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): Double = gsl_matrix_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: Double): Unit =
-        gsl_matrix_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslRealMatrix {
         val new = requireNotNull(gsl_matrix_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_memcpy(new, nativeHandle)
+        gsl_matrix_memcpy(new, nativeHandleChecked())
         return GslRealMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslRealMatrix) return gsl_matrix_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslRealMatrix) return gsl_matrix_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -45,31 +45,31 @@ internal class GslFloatMatrix(
     scope: DeferScope
 ) : GslMatrix<Float, gsl_matrix_float>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslFloatMatrix =
-        GslFloatMatrix(nativeHandle, this.features + features, scope)
+        GslFloatMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): Float = gsl_matrix_float_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): Float = gsl_matrix_float_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: Float): Unit =
-        gsl_matrix_float_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_float_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslFloatMatrix {
         val new = requireNotNull(gsl_matrix_float_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_float_memcpy(new, nativeHandle)
+        gsl_matrix_float_memcpy(new, nativeHandleChecked())
         return GslFloatMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_float_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_float_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslFloatMatrix) return gsl_matrix_float_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslFloatMatrix) return gsl_matrix_float_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -80,31 +80,31 @@ internal class GslShortMatrix(
     scope: DeferScope
 ) : GslMatrix<Short, gsl_matrix_short>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslShortMatrix =
-        GslShortMatrix(nativeHandle, this.features + features, scope)
+        GslShortMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): Short = gsl_matrix_short_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): Short = gsl_matrix_short_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: Short): Unit =
-        gsl_matrix_short_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_short_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslShortMatrix {
         val new = requireNotNull(gsl_matrix_short_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_short_memcpy(new, nativeHandle)
+        gsl_matrix_short_memcpy(new, nativeHandleChecked())
         return GslShortMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_short_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_short_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslShortMatrix) return gsl_matrix_short_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslShortMatrix) return gsl_matrix_short_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -115,31 +115,31 @@ internal class GslUShortMatrix(
     scope: DeferScope
 ) : GslMatrix<UShort, gsl_matrix_ushort>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslUShortMatrix =
-        GslUShortMatrix(nativeHandle, this.features + features, scope)
+        GslUShortMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): UShort = gsl_matrix_ushort_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): UShort = gsl_matrix_ushort_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: UShort): Unit =
-        gsl_matrix_ushort_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_ushort_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslUShortMatrix {
         val new = requireNotNull(gsl_matrix_ushort_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_ushort_memcpy(new, nativeHandle)
+        gsl_matrix_ushort_memcpy(new, nativeHandleChecked())
         return GslUShortMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_ushort_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_ushort_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslUShortMatrix) return gsl_matrix_ushort_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslUShortMatrix) return gsl_matrix_ushort_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -150,31 +150,31 @@ internal class GslLongMatrix(
     scope: DeferScope
 ) : GslMatrix<Long, gsl_matrix_long>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslLongMatrix =
-        GslLongMatrix(nativeHandle, this.features + features, scope)
+        GslLongMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): Long = gsl_matrix_long_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): Long = gsl_matrix_long_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: Long): Unit =
-        gsl_matrix_long_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_long_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslLongMatrix {
         val new = requireNotNull(gsl_matrix_long_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_long_memcpy(new, nativeHandle)
+        gsl_matrix_long_memcpy(new, nativeHandleChecked())
         return GslLongMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_long_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_long_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslLongMatrix) return gsl_matrix_long_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslLongMatrix) return gsl_matrix_long_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -185,31 +185,31 @@ internal class GslULongMatrix(
     scope: DeferScope
 ) : GslMatrix<ULong, gsl_matrix_ulong>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslULongMatrix =
-        GslULongMatrix(nativeHandle, this.features + features, scope)
+        GslULongMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): ULong = gsl_matrix_ulong_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): ULong = gsl_matrix_ulong_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: ULong): Unit =
-        gsl_matrix_ulong_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_ulong_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslULongMatrix {
         val new = requireNotNull(gsl_matrix_ulong_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_ulong_memcpy(new, nativeHandle)
+        gsl_matrix_ulong_memcpy(new, nativeHandleChecked())
         return GslULongMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_ulong_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_ulong_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslULongMatrix) return gsl_matrix_ulong_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslULongMatrix) return gsl_matrix_ulong_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -220,31 +220,31 @@ internal class GslIntMatrix(
     scope: DeferScope
 ) : GslMatrix<Int, gsl_matrix_int>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslIntMatrix =
-        GslIntMatrix(nativeHandle, this.features + features, scope)
+        GslIntMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): Int = gsl_matrix_int_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): Int = gsl_matrix_int_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: Int): Unit =
-        gsl_matrix_int_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_int_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslIntMatrix {
         val new = requireNotNull(gsl_matrix_int_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_int_memcpy(new, nativeHandle)
+        gsl_matrix_int_memcpy(new, nativeHandleChecked())
         return GslIntMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_int_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_int_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslIntMatrix) return gsl_matrix_int_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslIntMatrix) return gsl_matrix_int_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }
@@ -255,31 +255,31 @@ internal class GslUIntMatrix(
     scope: DeferScope
 ) : GslMatrix<UInt, gsl_matrix_uint>(scope) {
     override val rowNum: Int
-        get() = nativeHandle.pointed.size1.toInt()
+        get() = nativeHandleChecked().pointed.size1.toInt()
 
     override val colNum: Int
-        get() = nativeHandle.pointed.size2.toInt()
+        get() = nativeHandleChecked().pointed.size2.toInt()
 
     override val features: Set<MatrixFeature> = features
 
     override fun suggestFeature(vararg features: MatrixFeature): GslUIntMatrix =
-        GslUIntMatrix(nativeHandle, this.features + features, scope)
+        GslUIntMatrix(nativeHandleChecked(), this.features + features, scope)
 
-    override operator fun get(i: Int, j: Int): UInt = gsl_matrix_uint_get(nativeHandle, i.toULong(), j.toULong())
+    override operator fun get(i: Int, j: Int): UInt = gsl_matrix_uint_get(nativeHandleChecked(), i.toULong(), j.toULong())
 
     override operator fun set(i: Int, j: Int, value: UInt): Unit =
-        gsl_matrix_uint_set(nativeHandle, i.toULong(), j.toULong(), value)
+        gsl_matrix_uint_set(nativeHandleChecked(), i.toULong(), j.toULong(), value)
 
     override fun copy(): GslUIntMatrix {
         val new = requireNotNull(gsl_matrix_uint_alloc(rowNum.toULong(), colNum.toULong()))
-        gsl_matrix_uint_memcpy(new, nativeHandle)
+        gsl_matrix_uint_memcpy(new, nativeHandleChecked())
         return GslUIntMatrix(new, features, scope)
     }
 
-    override fun close(): Unit = gsl_matrix_uint_free(nativeHandle)
+    override fun close(): Unit = gsl_matrix_uint_free(nativeHandleChecked())
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslUIntMatrix) return gsl_matrix_uint_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslUIntMatrix) return gsl_matrix_uint_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 }

kmath-gsl/src/nativeMain/kotlin/kscience/kmath/gsl/_Vectors.kt

@@ -6,176 +6,176 @@ import org.gnu.gsl.*
 internal class GslRealVector(override val nativeHandle: CPointer<gsl_vector>, scope: DeferScope) : 
     GslVector<Double, gsl_vector>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): Double = gsl_vector_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: Double): Unit = gsl_vector_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): Double = gsl_vector_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: Double): Unit = gsl_vector_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslRealVector {
         val new = requireNotNull(gsl_vector_alloc(size.toULong()))
-        gsl_vector_memcpy(new, nativeHandle)
+        gsl_vector_memcpy(new, nativeHandleChecked())
         return GslRealVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslRealVector) return gsl_vector_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslRealVector) return gsl_vector_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_free(nativeHandleChecked())
 }
 
 internal class GslFloatVector(override val nativeHandle: CPointer<gsl_vector_float>, scope: DeferScope) : 
     GslVector<Float, gsl_vector_float>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): Float = gsl_vector_float_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: Float): Unit = gsl_vector_float_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): Float = gsl_vector_float_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: Float): Unit = gsl_vector_float_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslFloatVector {
         val new = requireNotNull(gsl_vector_float_alloc(size.toULong()))
-        gsl_vector_float_memcpy(new, nativeHandle)
+        gsl_vector_float_memcpy(new, nativeHandleChecked())
         return GslFloatVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslFloatVector) return gsl_vector_float_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslFloatVector) return gsl_vector_float_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_float_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_float_free(nativeHandleChecked())
 }
 
 internal class GslShortVector(override val nativeHandle: CPointer<gsl_vector_short>, scope: DeferScope) : 
     GslVector<Short, gsl_vector_short>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): Short = gsl_vector_short_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: Short): Unit = gsl_vector_short_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): Short = gsl_vector_short_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: Short): Unit = gsl_vector_short_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslShortVector {
         val new = requireNotNull(gsl_vector_short_alloc(size.toULong()))
-        gsl_vector_short_memcpy(new, nativeHandle)
+        gsl_vector_short_memcpy(new, nativeHandleChecked())
         return GslShortVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslShortVector) return gsl_vector_short_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslShortVector) return gsl_vector_short_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_short_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_short_free(nativeHandleChecked())
 }
 
 internal class GslUShortVector(override val nativeHandle: CPointer<gsl_vector_ushort>, scope: DeferScope) : 
     GslVector<UShort, gsl_vector_ushort>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): UShort = gsl_vector_ushort_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: UShort): Unit = gsl_vector_ushort_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): UShort = gsl_vector_ushort_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: UShort): Unit = gsl_vector_ushort_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslUShortVector {
         val new = requireNotNull(gsl_vector_ushort_alloc(size.toULong()))
-        gsl_vector_ushort_memcpy(new, nativeHandle)
+        gsl_vector_ushort_memcpy(new, nativeHandleChecked())
         return GslUShortVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslUShortVector) return gsl_vector_ushort_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslUShortVector) return gsl_vector_ushort_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_ushort_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_ushort_free(nativeHandleChecked())
 }
 
 internal class GslLongVector(override val nativeHandle: CPointer<gsl_vector_long>, scope: DeferScope) : 
     GslVector<Long, gsl_vector_long>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): Long = gsl_vector_long_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: Long): Unit = gsl_vector_long_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): Long = gsl_vector_long_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: Long): Unit = gsl_vector_long_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslLongVector {
         val new = requireNotNull(gsl_vector_long_alloc(size.toULong()))
-        gsl_vector_long_memcpy(new, nativeHandle)
+        gsl_vector_long_memcpy(new, nativeHandleChecked())
         return GslLongVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslLongVector) return gsl_vector_long_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslLongVector) return gsl_vector_long_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_long_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_long_free(nativeHandleChecked())
 }
 
 internal class GslULongVector(override val nativeHandle: CPointer<gsl_vector_ulong>, scope: DeferScope) : 
     GslVector<ULong, gsl_vector_ulong>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): ULong = gsl_vector_ulong_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: ULong): Unit = gsl_vector_ulong_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): ULong = gsl_vector_ulong_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: ULong): Unit = gsl_vector_ulong_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslULongVector {
         val new = requireNotNull(gsl_vector_ulong_alloc(size.toULong()))
-        gsl_vector_ulong_memcpy(new, nativeHandle)
+        gsl_vector_ulong_memcpy(new, nativeHandleChecked())
         return GslULongVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslULongVector) return gsl_vector_ulong_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslULongVector) return gsl_vector_ulong_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_ulong_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_ulong_free(nativeHandleChecked())
 }
 
 internal class GslIntVector(override val nativeHandle: CPointer<gsl_vector_int>, scope: DeferScope) : 
     GslVector<Int, gsl_vector_int>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): Int = gsl_vector_int_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: Int): Unit = gsl_vector_int_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): Int = gsl_vector_int_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: Int): Unit = gsl_vector_int_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslIntVector {
         val new = requireNotNull(gsl_vector_int_alloc(size.toULong()))
-        gsl_vector_int_memcpy(new, nativeHandle)
+        gsl_vector_int_memcpy(new, nativeHandleChecked())
         return GslIntVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslIntVector) return gsl_vector_int_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslIntVector) return gsl_vector_int_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_int_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_int_free(nativeHandleChecked())
 }
 
 internal class GslUIntVector(override val nativeHandle: CPointer<gsl_vector_uint>, scope: DeferScope) : 
     GslVector<UInt, gsl_vector_uint>(scope) {
     override val size: Int
-        get() = nativeHandle.pointed.size.toInt()
+        get() = nativeHandleChecked().pointed.size.toInt()
 
-    override fun get(index: Int): UInt = gsl_vector_uint_get(nativeHandle, index.toULong())
-    override fun set(index: Int, value: UInt): Unit = gsl_vector_uint_set(nativeHandle, index.toULong(), value)
+    override fun get(index: Int): UInt = gsl_vector_uint_get(nativeHandleChecked(), index.toULong())
+    override fun set(index: Int, value: UInt): Unit = gsl_vector_uint_set(nativeHandleChecked(), index.toULong(), value)
 
     override fun copy(): GslUIntVector {
         val new = requireNotNull(gsl_vector_uint_alloc(size.toULong()))
-        gsl_vector_uint_memcpy(new, nativeHandle)
+        gsl_vector_uint_memcpy(new, nativeHandleChecked())
         return GslUIntVector(new, scope)
     }
 
     override fun equals(other: Any?): Boolean {
-        if (other is GslUIntVector) return gsl_vector_uint_equal(nativeHandle, other.nativeHandle) == 1
+        if (other is GslUIntVector) return gsl_vector_uint_equal(nativeHandleChecked(), other.nativeHandleChecked()) == 1
         return super.equals(other)
     }
 
-    override fun close(): Unit = gsl_vector_uint_free(nativeHandle)
+    override fun close(): Unit = gsl_vector_uint_free(nativeHandleChecked())
 }
 

kmath-gsl/src/nativeTest/kotlin/ErrorsHandlingTest.kt

@@ -4,7 +4,7 @@ import org.gnu.gsl.gsl_block_calloc
 import kotlin.test.Test
 import kotlin.test.assertFailsWith
 
-internal class ErrorHandler {
+internal class ErrorsHandlingTest {
     @Test
     fun blockAllocation() {
         assertFailsWith<GslException> {
@@ -19,4 +19,14 @@ internal class ErrorHandler {
             GslRealMatrixContext { produce(Int.MAX_VALUE, Int.MAX_VALUE) { _, _ -> 0.0 } }
         }
     }
+
+    @Test
+    fun useOfClosedObject() {
+        val mat = GslRealMatrixContext { produce(1, 1) { _, _ -> 0.0 } }
+        assertFailsWith<IllegalStateException> { mat.colNum }
+        assertFailsWith<IllegalStateException> { mat.rowNum }
+        assertFailsWith<IllegalStateException> { mat[0, 0] }
+        assertFailsWith<IllegalStateException> { mat.copy() }
+        assertFailsWith<IllegalStateException> { println(mat == mat) }
+    }
 }

kmath-gsl/src/nativeTest/kotlin/GslMatrixRealTest.kt

@@ -1,5 +1,9 @@
 package kscience.kmath.gsl
 
+import kscience.kmath.linear.RealMatrixContext
+import kscience.kmath.operations.invoke
+import kscience.kmath.structures.Matrix
+import kotlin.random.Random
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
@@ -16,4 +20,23 @@ internal class GslMatrixRealTest {
         val mat = produce(1, 1) { _, _ -> 42.0 }
         assertEquals(42.0, mat[0, 0])
     }
+
+    @Test
+    fun copy() = GslRealMatrixContext {
+        val mat = produce(1, 1) { _, _ -> 42.0 }
+        assertEquals(mat, mat.copy())
+    }
+
+    @Test
+    fun equals() = GslRealMatrixContext {
+        var rng = Random(0)
+        val mat: Matrix<Double> = produce(2, 2) { _, _ -> rng.nextDouble() }
+        rng = Random(0)
+        val mat2: Matrix<Double> = RealMatrixContext { produce(2, 2) { _, _ -> rng.nextDouble() } }
+        rng = Random(0)
+        val mat3: Matrix<Double> = produce(2, 2) { _, _ -> rng.nextDouble() }
+        assertEquals(mat, mat2)
+        assertEquals(mat, mat3)
+        assertEquals(mat2, mat3)
+    }
 }

kmath-gsl/src/nativeTest/kotlin/GslRealMatrixContextTest.kt

@@ -3,7 +3,6 @@ package kscience.kmath.gsl
 import kscience.kmath.linear.RealMatrixContext
 import kscience.kmath.operations.invoke
 import kscience.kmath.structures.Matrix
-import kscience.kmath.structures.NDStructure
 import kscience.kmath.structures.RealBuffer
 import kscience.kmath.structures.asSequence
 import kotlin.random.Random
@@ -12,11 +11,11 @@ import kotlin.test.assertEquals
 import kotlin.test.assertTrue
 import kotlin.time.measureTime
 
-internal class GslRealContextTest {
+internal class GslRealMatrixContextTest {
     @Test
     fun testScale() = GslRealMatrixContext {
         val ma = produce(10, 10) { _, _ -> 0.1 }
-        val mb = (ma * 20.0)
+        val mb = ma * 20.0
         assertEquals(mb[0, 1], 2.0)
     }
 
@@ -42,7 +41,7 @@ internal class GslRealContextTest {
 
     @Test
     fun testManyCalls() = GslRealMatrixContext {
-        val expected = RealMatrixContext {
+        val expected: Matrix<Double> = RealMatrixContext {
             val rng = Random(0)
             var prod = produce(20, 20) { _, _ -> rng.nextDouble() }
             val mult = produce(20, 20) { _, _ -> rng.nextDouble() }
@@ -51,9 +50,9 @@ internal class GslRealContextTest {
         }
 
         val rng = Random(0)
-        var prod = produce(20, 20) { _, _ -> rng.nextDouble() }
+        var prod: Matrix<Double> = produce(20, 20) { _, _ -> rng.nextDouble() }
         val mult = produce(20, 20) { _, _ -> rng.nextDouble() }
         measureTime { repeat(100) { prod = prod dot mult } }.also(::println)
-        assertTrue(NDStructure.equals(expected, prod))
+        assertEquals(expected, prod)
     }
 }