您可以通过向任务调用添加符号参数来指定 rake 中的形式参数。例如:
require 'rake'
task :my_task, [:arg1, :arg2] do |t, args|
puts "Args were: #{args} of class #{args.class}"
puts "arg1 was: '#{args[:arg1]}' of class #{args[:arg1].class}"
puts "arg2 was: '#{args[:arg2]}' of class #{args[:arg2].class}"
end
task :invoke_my_task do
Rake.application.invoke_task("my_task[1, 2]")
end
# or if you prefer this syntax...
task :invoke_my_task_2 do
Rake::Task[:my_task].invoke(3, 4)
end
# a task with prerequisites passes its
# arguments to it prerequisites
task :with_prerequisite, [:arg1, :arg2] => :my_task #<- name of prerequisite task
# to specify default values,
# we take advantage of args being a Rake::TaskArguments object
task :with_defaults, :arg1, :arg2 do |t, args|
args.with_defaults(:arg1 => :default_1, :arg2 => :default_2)
puts "Args with defaults were: #{args}"
end
然后,从命令行:
> rake my_task[1,false]
Args were: {:arg1=>"1", :arg2=>"false"} of class Rake::TaskArguments
arg1 was: '1' of class String
arg2 was: 'false' of class String
> rake "my_task[1, 2]"
Args were: {:arg1=>"1", :arg2=>"2"}
> rake invoke_my_task
Args were: {:arg1=>"1", :arg2=>"2"}
> rake invoke_my_task_2
Args were: {:arg1=>3, :arg2=>4}
> rake with_prerequisite[5,6]
Args were: {:arg1=>"5", :arg2=>"6"}
> rake with_defaults
Args with defaults were: {:arg1=>:default_1, :arg2=>:default_2}
> rake with_defaults['x','y']
Args with defaults were: {:arg1=>"x", :arg2=>"y"}
如第二个示例所示,如果要使用空格,则需要在目标名称周围加上引号,以防止 shell 在空格处拆分参数。
查看中的代码rake.rb,看来 rake 不会解析任务字符串来提取先决条件的参数,所以你不能这样做task :t1 => "dep[1,2]"
。为先决条件指定不同参数的唯一方法是在依赖任务操作中显式调用它,如:invoke_my_task
and :invoke_my_task_2
.
请注意,某些 shell(如 zsh)要求您转义括号:rake my_task\['arg1'\]