Add and update manual pages for slicing, indexing, and reshaping.
diff --git a/doc/snippets/Slicing_arrayexpr.cpp b/doc/snippets/Slicing_arrayexpr.cpp
new file mode 100644
index 0000000..00b689b
--- /dev/null
+++ b/doc/snippets/Slicing_arrayexpr.cpp
@@ -0,0 +1,4 @@
+ArrayXi ind(5); ind<<4,2,5,5,3;
+MatrixXi A = MatrixXi::Random(4,6);
+cout << "Initial matrix A:\n" << A << "\n\n";
+cout << "A(all,ind-1):\n" << A(all,ind-1) << "\n\n";
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