Python assert, O Option

Use the assert statement to ensure a condition is true at runtime. The O option removes assert statements.

Assert. This statement causes an AssertionError when an expression is false. We pass an expression (or value) as the first argument. Python stops and signals the assert call.Error

With this statement, we can ensure a program's state is correct. And by providing the "O" option on the command line, we can optimize out all assert calls.

Tip: Assert() only has an effect when __debug__ is true. We can disable __debug__ with a command-line parameter.

An assert example. This example program has an assert statement. It causes an AssertionError unless the two values add up to 110.

So: If the two values add up to 110, an assertion occurs. Otherwise nothing happens.

Command lines: The first command line uses the "O" option. This means the assertion is optimized out of the program.

And: The second command line uses no special options, so the assert is left in the program and triggered.

Python program that uses assert value = 10 value2 = 100 # Assert if this expression is not true. assert(value + value2 != 110) print("DONE") Command line: C:\pypy3-2.4.0-win32\pypy.exe -O C:\programs\file.py Output DONE Command line: C:\pypy3-2.4.0-win32\pypy.exe C:\programs\file.py Output Traceback (most recent call last): File "C:\programs\file.py", line 8, in <module> assert(value + value2 != 110) AssertionError

Options. When running PyPy or Python, try providing the "-h" option. This will show you help. Then use "-O" to enable optimization (which removes asserts).

Options: -O : skip assert statements

Some notes. Python is not known for its extreme performance. If your code is critical and cannot bear the burden of assert statements, a faster language might be a good idea.

Research. The Python site indicates that assert statements are removed when optimization is enabled. So performance is not affected.

Quote: The current code generator emits no code for an assert statement when optimization is requested at compile-time.

Simple statements: python.org

A review. Assert statements can be used instead of print statements for debugging. With assert() we can then completely remove all this logic. This helps if we know the program is correct.Built-ins

The Dev Codes

.Net

.NET Array Dictionary List String 2D Async DataTable Dates DateTime Enum File For Foreach Format IEnumerable If IndexOf Lambda LINQ Parse Path Process Property Regex Replace Sort Split Static StringBuilder Substring Switch Tuple

Java

Core Array ArrayList HashMap String 2D Cast Character Console Deque Duplicates File For Format HashSet If IndexOf Lambda Math ParseInt Process Random Regex Replace Sort Split StringBuilder Substring Switch Vector While

Related Links

Adjectives Ado Ai Android Angular Antonyms Apache Articles Asp Autocad Automata Aws Azure Basic Binary Bitcoin Blockchain C Cassandra Change Coa Computer Control Cpp Create Creating C-Sharp Cyber Daa Data Dbms Deletion Devops Difference Discrete Es6 Ethical Examples Features Firebase Flutter Fs Git Go Hbase History Hive Hiveql How Html Idioms Insertion Installing Ios Java Joomla Js Kafka Kali Laravel Logical Machine Matlab Matrix Mongodb Mysql One Opencv Oracle Ordering Os Pandas Php Pig Pl Postgresql Powershell Prepositions Program Python React Ruby Scala Selecting Selenium Sentence Seo Sharepoint Software Spellings Spotting Spring Sql Sqlite Sqoop Svn Swift Synonyms Talend Testng Types Uml Unity Vbnet Verbal Webdriver What Wpf

TheDeveloperBlog.com

Python assert, O Option

Related Links:

.Net

Java

Related Links