From: ptkwt@... (Phil Tomson)
Date: 2004-06-22T07:13:13+09:00
Subject: Rake and timestamps (ideoms or methods?)


Here's my rakefile:

#begin rakefile
task :default => [ :sim_jtag_tb ] do
  puts "done..."
end

task :sim_jtag_tb => [ :build_jtag_tb ] do
  puts "simulate it..."
  system("ncsim -gui jtag_tb:jtag_tb_behavior")
end

task :build_jtag_tb => [ :build_jtag, :build_jtag_driver ] do
  puts "build jtag_tb"
  raise "jtag_tb_c build failed " unless system("ncvhdl -linedebug 
jtag_tb_c.vhd")
  raise "jtag_tb_c build failed " unless system("ncelab 
jtag_tb:jtag_tb_behavior -access +r+w")
end

task :build_jtag_driver do
  puts "build jtag_driver"
  raise "build_jtag_driver failed" unless system("ncvhdl -linedebug 
jtag_driver.vhd")
end

task :build_jtag do
  puts "build jtag..."
  raise "build_jtag failed" unless system("ncvhdl -linedebug jtag.vhd")
end

#end of rakefile

If I don't want to run certain tasks if the file the task is to work on 
already is up-to-date (like how make works) how do I tell Rake to not 
execute a particular task if the files being worked on are up-to-date?  Is 
there some built-in way of doing this (by listing the dependent files) or 
do you have to do that yourself?

Also, notice the 'raise "blah" system("command")' that I'm doing above. I 
want the whole thing to just die if one of the dependencies couldn't be 
built (as in make) -  is there some builtin method for doing this as well?  

Are these things just handled 'ideomatically' in Rake now (as opposed 
to their being built-in methods for them)?

Phil