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Functional Python Programming

Functional Python Programming

By : Steven F. Lott
4 (9)
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Functional Python Programming

Functional Python Programming

4 (9)
By: Steven F. Lott

Overview of this book

This book is for developers who want to use Python to write programs that lean heavily on functional programming design patterns. You should be comfortable with Python programming, but no knowledge of functional programming paradigms is needed.
Table of Contents (18 chapters)
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17
Index

The iter() function with a sentinel value


The built-in iter() function creates an iterator over a collection object. We can use this to wrap an iterator object around a collection. In many cases, we'll allow the for statement to handle this implicitly. In a few cases, we might want to create an iterator explicitly so that we can separate the head from the tail of a collection. This function can also iterate through the values created by a callable or function until a sentinel value is found. This feature is sometimes used with the read() function of a file to consume rows until some sentinel value is found. In this case, the given function might be some file's readline() method. Providing a callable function to iter() is a bit hard for us because this function must maintain state internally. This hidden state is a feature of an open file, for example, each read() or readline() function advances some internal state to the next character or next line.

Another example of this is the way that...

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