Merge topic 'doc-CMP0054-example'
9535b86d
Help: Replace CMP0054 example to show when it makes a difference
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@ -16,29 +16,33 @@ Given the following partial example:
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::
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set(MONKEY 1)
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set(ANIMAL MONKEY)
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set(A E)
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set(E "")
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if("${ANIMAL}" STREQUAL "MONKEY")
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if("${A}" STREQUAL "")
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message("Result is TRUE before CMake 3.1 or when CMP0054 is OLD")
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else()
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message("Result is FALSE in CMake 3.1 and above if CMP0054 is NEW")
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endif()
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After explicit expansion of variables this gives:
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::
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if("MONKEY" STREQUAL "MONKEY")
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if("E" STREQUAL "")
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With the policy set to ``OLD`` implicit expansion reduces this semantically to:
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::
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if("1" STREQUAL "1")
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if("" STREQUAL "")
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With the policy set to ``NEW`` the quoted arguments will not be
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further dereferenced:
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::
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if("MONKEY" STREQUAL "MONKEY")
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if("E" STREQUAL "")
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This policy was introduced in CMake version 3.1.
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CMake version |release| warns when the policy is not set and uses
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