Angel Lam

Coding Projects

These are the littles things I learnt as a programmer and notes to help me(and others) grow as better engineers:

Windows:

Windows is case insensitive. When developing cross platform a folder/file can be created in Linux that may not be valid on Windows and can cause issues (ie: disappearing directories when os.remove deletes both "folder_A" and "folder_a")!

Maya:

Web:

Declare variables with "Let" and "Const" to limit their scope rather than "var". More Info
"window.localstorage.var" is the same as "localstorage.var". But having the preceding "window" notifies it as a global variable.

Python:

Print "module.__file__" to troubleshoot and see which module/file is being used.
Python needs __init__.py files (can be empty) in directories with modules so that we can do "import dir.module".
QPixmap shouldn't be in threads but QImage can (no GUI error). But QImage is optimized for image manipulation and QPixmap is the best for displaying images.
Partial is static meaning it doesn't need to resolve again and will be faster than lambda. Example: when calling a function when a Pyqt button is pressed, if the arguments to the function are the same, use partial.
Can do: "a, b = [list]" instead of "a=list[0], b=list[1]" if we are sure that list has 2 values.
Use QSettings to make your Pyqt App remember values/settings.
Pyqt can set "QT_PREFERRED_BINDING" for qt version to use when developing/deploying in multiple environments.
ui.exec() freezes other windows and ui.show() doesn't. Dialog documentation.
"dir(object)" will print out attributes available for that object. Helpful when working with modules with very little documentation.
Logging module: Use % formating instead of format because logger automatically formats it ie: "logger.info("%s %s", string_one, string_two)"
Python doesn't automatically deep copy objects, it'll keep a reference to that object when assigned to a variable.
Use "__repr__" to help debug because printing an Object can be confusing. A Representation gives more comprehensive information.
Check function description formats with this.

Other Tips and Tricks:

Returning a function instead of calling a function (anonymous function) can be useful when you want to run a function later in a higher function (Often used in with RV Plugins).
Declare global variables outside of a class when you want to access those variables before initializing a class in a module.
Declare Static Variables (ie: "@Staticmethod" with @Setters in Python) for methods that makes sense inside a class, but don't need an instance of a class for it to work.
When checking booleans, use "is True" instead of just "is variable_name" if the variable type is a Boolean. "is variable_name" can mean 0, False and None.
SQL: use "EXIST" rather than "COUNT" when you don't need the value of a query because "EXIST" stops once True, but "COUNT" iterates through all of the data.