Examples of functions Exists(.) and GetForced(.)

demos/struct/Exists_GetForced.geo

+//
+// Functions: Exists(.) and GetForced(.)
+//   (for both Gmsh and GetDP)
+//
+
+val_real = 12;
+
+list_of_real() = {11 ,22, 33};
+
+Struct namespace::struct_name [ Dim 2, Ref 5 ]; // See file struct.geo for Struct definitions
+
+// Look at the Current Workspace for checking the variables contents.
+
+//
+// Function Exists(name_variable):
+//   returns 1 if variable 'name_variable' exists, 0 if not
+
+If (Exists(val_real))
+  Printf("Variable 'val_real' exists");
+EndIf
+
+If (!Exists(other_val_real))
+  Printf("Variable 'other_val_real' does not exist");
+EndIf
+
+If (Exists(list_of_real))
+  Printf("List 'list_of_real()' exists");
+EndIf
+
+If (Exists(namespace::struct_name.Dim))
+  Printf("Member 'Dim' of structure 'namespace::struct_name' exists");
+EndIf
+
+If (!Exists(namespace::struct_name.Thickness))
+  Printf("Member 'Thickness' of structure 'namespace::struct_name' does not exist");
+  Struct namespace::struct_name (Append) [ Thickness 0.01 ]; // This member is added to the structure
+  If (Exists(namespace::struct_name.Thickness))
+    Printf("Member 'Thickness' of structure 'namespace::struct_name' now exists");
+  EndIf
+EndIf
+
+//
+// GetForced(name_variable, default_value):
+//   returns value of 'name_variable' if it exists, default_value if not
+// GetForced(name_variable):
+//   returns value of 'name_variable' if it exists, 0 (zero) if not
+
+get_forced_val_real = GetForced(val_real, 1); // Will be 12, the value of the existing  variable
+
+get_forced_other_val_real_with_defined_default_value = GetForced(other_val_real, 1); // Will be 1 (defined default value) because variable does not exist
+get_forced_other_val_real_with_zero_default_value = GetForced(other_val_real); // Will be 0 (default value) because variable does not exist
+
+get_forced_struct_member_with_default = GetForced(namespace::struct_name.InexistingMember, -1); // Will be the defined default value -1
+
+//