title: How do I make a target in a makefile invoke another target in the makefile
body: <p>So I have this makefile and I want the target all just  to invoke the target expertest, but apparently the way I'm doing it is wrong because i'm getting the error 
  "make: exprtest: Command not found
  make: <em>*</em> [all] Error 127
  "
  this is the makefile:</p>
  
  <pre><code>all:
      exprtest
  exprtest: exptrtest.o driver.o parser.tab.o scanner.o
      g++ -Wall -g -o exprtest exptrtest.o driver.o parser.tab.o scanner.o
  driver.o: driver.cpp scanner.hpp driver.hpp
      g++ -Wall -g -c driver.cpp
  parser.tab.o: parser.tab.hpp parser.tab.cpp
      bison parser.ypp
      g++ -Wall -g -c parser.tab.cpp
  scanner.o: scanner.cpp scanner.hpp
      flex -t scanner.ll &gt; scanner.cpp
      g++ -Wall -g -c scanner.cpp
  clean:
      rm parser.tab.hpp parser.tab.cpp scanner.cpp
  </code></pre>