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### Debug a runnable
This video shows how a [runnable module](features_runnables) can be debugged in the [GDB commander](widgets_gdb_commander) widget.
The runnable calls a function that returns an `int`.
A breakpoint is put before returning and the result is patched in the CPU inspector by changing RAX value.
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### GIT gui as a tool
This video shows how to setup a [custom tool](widgets_custom_tools) that invokes `git gui` for the current project.
The trick is to set the tool's current working directory with a [symbolic string](features_symbolic_strings) that's expanded to the current project location.
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### Compiler paths
This video shows how it's easy to [select a specific D compiler](options_compilers_paths) on the fly: official dmd, upstream dmd, ldc and gdc.
Here the choice is applied to the compiler used to make a runnable but the same setting also exists for the projects.
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### Library manager and runnables
This video shows how a DUB library can be downloaded, installed and used directly in a [runnable](features_runnables) module.
The most important operations are made in the [library manager](widgets_library_manager).
At the end and to make obvious the automatic aspect of a library selection, the runnable is compiled while the new libman entry is deactivated, which results in a compiler error.
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### Programming sessions - parse enum in YATOL
This video shows a full programming session during which i add a new grammar construct to my [toy programming language](https://github.com/BBasile/yatol).
There are 3 parts:
1. The formal grammar (i use a PEG that can be used in [Pegged](https://github.com/PhilippeSigaud/Pegged)) is updated.
2. The hand written parser is updated.
3. Changes are pushed on line and i wait for TravisCI to start (which didn't happen !).
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The video illustrate well that the [runnable](features_runnables) modules (the command Run module unittest is a subset of the feature) are valuable.
The PEG can be tested on the fly because pegged is registered in the [library manager](widgets_library_manager).
The parser can be tested on the fly because the compiler (as a library) is registered in the [library manager](widgets_library_manager).
The custom tools allows to easily push changes online.
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