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contrib/macros/Merge.md

+**CAUTION: The contents of this page may be obsolete**
+![120px-Old_finnish_stop_sign.svg](/uploads/521180f925eeefd545a3a7a761185c2e/120px-Old_finnish_stop_sign.svg.png)
+
+----
+
+[Back](CMake_User_Contributed_Macros "wikilink")
+
+**NOTE:** You can merge and sort lists using the SET() and LIST()
+command and no longer need this macro.
+
+    set(FIRST_LIST  a b c d i j k l)
+    set(SECOND_LIST e f g h m n o p)
+    set(COMPLETE_LIST ${FIRST_LIST} ${SECOND_LIST})
+    list(SORT COMPLETE_LIST)
+    # you can also remove duplicates
+    list(REMOVE_DUPLICATES COMPLETE_LIST)
+
+-----
+
+    # This macro merges elements in sorted lists ALIST and BLIST and stored the result in OUTPUT
+    MACRO(MERGE ALIST BLIST OUTPUT)
+    SET(BTEMP ${BLIST})
+    FOREACH(A ${ALIST})
+        SET(SORTED)
+        SET(UNINSERTED 1)
+        FOREACH(B ${BTEMP})
+            IF(${UNINSERTED})
+                IF(${A} STRLESS ${B})
+                    SET(SORTED ${SORTED} ${A})
+                    SET(UNINSERTED 0)
+                ENDIF(${A} STRLESS ${B})
+            ENDIF(${UNINSERTED})
+            SET(SORTED ${SORTED} ${B})
+        ENDFOREACH(B ${BLIST})
+        IF(${UNINSERTED})
+            SET(SORTED ${SORTED} ${A})
+        ENDIF(${UNINSERTED})
+        SET(BTEMP ${SORTED})
+    ENDFOREACH(A ${ALIST})
+    SET(${OUTPUT} ${BTEMP})
+    ENDMACRO(MERGE ALIST BLIST OUTPUT)
+
+    # Here is an example that merges *.cpp files and *.h files into a single sorted list
+    # This would be easier if FILE(GLOB...) properly matches "*.{cpp,h}"
+    FILE(GLOB ALGEBRAIC_SRCS Implicit/Algebraic/*.cpp)
+    FILE(GLOB ALGEBRAIC_H Implicit/Algebraic/*.h)
+    MERGE("${ALGEBRAIC_H}" "${ALGEBRAIC_SRCS}" ALGEBRAIC_SRCS)
+
+[Back](CMake_User_Contributed_Macros "wikilink")
+
+
+----
+This page was initially populated by conversion from its [original location](https://public.kitware.com/Wiki/CMakeMacroMerge) in another wiki.