monasca-analytics/monasca_analytics/banana/deadpathck/README.md

Dead path checker

Dead path checking is about removing paths in the pipeline that lead to nothing. For instance, if there's no source or no sink in a path. This pass is the only one that modifies the AST.

This is the third step of the pipeline:

       +---------------------+                        +---------------------+
       |                     |                        |                     |
 --->  |   AST & TypeTable   | ---- deadpathck --->   |  AST' & TypeTable'  | --->
       |                     |                        |                     |
       +---------------------+                        +---------------------+

Current status:

• Remove branches that are dead from the list of connections.
• Remove the components from the collected list of components.
• Remove statements that are dead code:
  • Do not instantiate components.
  • Do not compute expressions for unused variables.