Syntaxcheck

For the full reference see: Syntaxcheck

Developing with Python in the web console can be a challenge. Sometimes a single change in a file will generate errors which have to be looked into with great care.

There is nothing but standard programmer’s work to alleviate the situation. But something was noticed during the development of AnPyLar and hence the tool anpylar-syntaxcheck.

• Sometimes small syntax errors produce messages which are difficult to decipher

Being able to catch the syntax error before you even test it, is therefore something to consider.

Let’s run it in our standard project structure

myapp
├── app
│   ├── __init__.py
│   ├── app_component.css
│   ├── app_component.html
│   ├── app_component.py
│   └── app_module.py
├── anpylar.js
├── index.html
├── package.json
└── styles.css

Change into myapp and run the command:

anpylar-syntaxcheck .

Because this is a standard clean project to start with, nothing happens. Let’s introduce an error in app_component.py

class AppComponent(Component):

    title = 'Tour of Pyroes'

    bindings = {
    }

    def render(self, node):
        print('hello' world)
        pass

And let’s re-run the command:

anpylar-syntaxcheck .

which issues the following output

File ".\app\app_component.py", line 15
  print('hello' world)
                    ^
SyntaxError: invalid syntax

And this allows to steadily correct the error and proceed with further development.

anpylar-syntaxcheck is not magic, it uses the built-in capabilities of the Python standard library (ast) to find the errors. It’s a small tool, but it can prove useful.