pattern matching - variable setting

[Aditya Kher]

How can I do something like this;

For case 1, I need CASE_DIR= /somewhere/case_1

For case 2, I need CASE_DIR=/somewhere/case_2

So I tried following makefile but it doesnot work.
What am I missing?
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%cat Makefile

case_%:CASE_DIR= /somewhere/case_%

case_%:
      @echo "The case directory is ${CASE_DIR}"
-----------------------------------
%gmake case_1
The case directory is /somewhere/case_%


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Aditya Kher
email: address@hidden
Web:   http://www.kher.org
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