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tutorials:beginner:process_modules [2016/01/22 16:54] – gkazhoyatutorials:beginner:process_modules [2016/01/25 11:30] – gkazhoya
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                                                    "action-designators"                                                    "action-designators"
                                                    "turtle-action-client"))))))                                                    "turtle-action-client"))))))
 +</code>
 +
 +Finally, let's also add '':cram-process-modules'' and ''cram-language-designator-support'' to the use list of our Lisp package for convenience:
 +<code lisp>
 +  (:use :cpl :roslisp :cl-transforms :cram-designators :cram-process-modules
 +        :cram-language-designator-support)
 </code> </code>
  
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 (in-package :tut) (in-package :tut)
  
-(cram-process-modules:def-process-module turtle-actuators (action-designator)+(def-process-module turtle-actuators (action-designator)
   (roslisp:ros-info (turtle-process-modules)   (roslisp:ros-info (turtle-process-modules)
                     "Turtle navigation invoked with action designator `~a'."                     "Turtle navigation invoked with action designator `~a'."
                     action-designator)                     action-designator)
-  (destructuring-bind (cmd action-goal) (reference action-designator) +  (destructuring-bind (command action-goal) (reference action-designator) 
-    (ecase cmd +    (ecase command 
-      (shape +      (draw-shape 
-         (call-shape-action +       (call-shape-action 
-          :edges (turtle-shape-edges action-goal) +        :edges (turtle-shape-edges action-goal) 
-          :radius (turtle-shape-radius action-goal))))))+        :radius (turtle-shape-radius action-goal)))))) 
 + 
 +(defmacro with-turtle-process-modules (&body body) 
 +  `(with-process-modules-running 
 +       (turtle-actuators) 
 +     ,@body))
 </code> </code>
  
-First, we use the ''cram-process-modules:def-process-module'' macro to define turtle-actuators as a process module taking one parameter (action-designator). The other lines in the def-process-module are comprise the code for turtle-actuators.+First, we use the ''cram-process-modules:def-process-module'' macro to define ''turtle-actuators'' as a process module taking one parameter (''action-designator''). The process module then chooses which action to perform depending on the command specified in the designator: ''destructuring-bind'' maps the results from ''(reference action-designator)'' to the variables ''command'' and ''action-goal'' respectively. Note that the inference rules we defined previously provide a name for the kind of action goal we have (currently, all are ''draw-shape''), and a ''turtle-shape'' object. We run an ''ecase'' on the kind of goal (currently, we only have the shape case) and use ''call-shape-action'' to tell the lower level to move the turtle around, given these parameters we infer from designator resolution.
  
-destructuring-bind will map the results from (reference action-designator) to the variables cmd and action-goal respectively. Note that the inference rules we defined previously provide a name for the kind of action goal we have (currently, all are "shape"), and a turtle-shape object. We run an ecase on the kind of goal (currently, we only have the shape case) and use the call-shape-action to tell the lower level to move the turtle around, given these parameters we infer from designator resolution.+The ''with-turtle-process-modules'' macro is a macro we define for convenience. It allows us to set up a context in which to run commands, knowing that the turtle process modules are all running concurrently. Right now we only have one defined, ''turtle-actuators''. When we will have several, we will add them to the list we pass to ''cram-process-modules:with-process-modules-running''. Note that the ''with-process-modules-running'' macro (and therefore ''with-turtle-process-modules'' too) needs to be run inside a ''top-level'' form. We will see this below.
  
-The with-turtle-process-modules macro is a macro we define for convenience. It allows us to set up a context in which to run commands, knowing that the turtle process modules are all running concurrently. Right now we only have one defined, turtle-actuators. When we will have several, we will add them to the list we pass to cpm:with-process-modules-running. Note that the cpm:with-process-modules-running macro (and therefore with-turtle-process-modules too) needs to be run inside a top-level macro. We will see this below. +Let's try this out. Make sure you have ''roscore'', ''turtlesim'', and ''turtle_actionlib'' running. In a terminal tab for each,
- +
-Let's try this out. Make sure you have roscore, turtlesim, and turtle_actionlib running. In a terminal tab for each,+
  
 <code> <code>
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 </code> </code>
  
-(**Note** on Oct. 21st 2014: you should check out then catkin_make the ROS common_tutorials from github to make sure you have the newest turtle_actionlib version available, otherwise the turtle might not move. To clone the ros_common tutorials, you will need to  +For convenience, let's append one more function to ''process-modules.lisp'' that will do all our calls for us:
- +
-<code> +
-git clone https://github.com/ros/common_tutorials +
-</code> +
- +
-inside the src folder of a ROS workspace, then catkin_make it.) +
- +
-For convenience, let's append one more function to process-modules.lisp that will do all our calls for us:+
  
 <code lisp> <code lisp>