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--- other:python:misc_by_jyp [2022/12/12 13:56]
jypeter Improved
+++ other:python:misc_by_jyp [2022/12/12 14:24]
jypeter Added the global variables section
@@ Line 254: / Line 254: @@
 Note: a configuration file is also a way to easily store and exchange text data !
+===== Working with global variables =====
+There is a good chance you don't actually want/need a //global// variable. Be sure to use the ''global'' statement correctly if you want to avoid side-effects...
+  * [[https://docs.python.org/3/faq/programming.html?highlight=global#why-am-i-getting-an-unboundlocalerror-when-the-variable-has-a-value|Using (and changing) a global variable inside a script or module]]
+    * Simple module example\\ <code>_myvar = 10
+def set_myvar(new_val):
+    # Note: need to explicitly define a global variable (of a module)
+    # as 'global' BEFORE changing its value in a function!
+    # Otherwise, the value will not be REdefined outside the function
+    global _myvar
+    _myvar = new_val
+def get_myvar():
+    return _myvar
+def myfunc(nb_repeat = 10):
+    print(nb_repeat * _myvar)</code>
+  * [[https://docs.python.org/3/faq/programming.html?highlight=global#how-do-i-share-global-variables-across-modules|Sharing global variables across modules]]
 ===== Sorting =====

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