Why I Love Python

The language you speak affects what you can think

Python is what I use the most to solve my own problems (I think better)

Including CGI/e-commerce with MySQL

5-10 times productivity (really!)

I’ve been trying to figure out how to explain “why” to people

Top 10 reasons I’ve come up with

And a few other interesting topics

What I love most: Python is about ME

As if Guido said: “Bruce, what can we do to make your programming experience as easy as possible?”

No compromises: it’s all about making me more productive

My Language History

Age 13: BASIC on HP1000 (HOSRAC.BAS is invented)

Age 19: APL for physics. The concept of a "terse language".

Basic again, survey courses, Pascal et al.

Age 21: Computer engineering, Chips + assembly language

Age 22: I begin to understand the value of high-level languages

Age 24: Database programming AppleII Basic

Age 25: Graduate (finally) with MS, discover C, work in embedded programming (in assembly).

I am my own C compiler

Age 26: Basic (again) for data analysis and control of wind-tunnel experiments

Age 27: Embedded C development. Program 4-bit Harvard architecture machine in assembly.

Wrote Assembler in GNU-Lisp. Created (?) primitive C++ mode for Gnu-emacs

Start writing for Micro Cornucopia

Age 29: University of Washington School of Oceanography with Tom Keffer.

Chose C++ over Objective-C for openness.

Published “Computer Interfacing with Pascal & C”

Age 32: Publish “Using C++”

Join ANSI C++ Committee

Later: “C++ Inside & Out”, “Black-Belt C++” (edited), “Thinking in C++”

Java: “easy translation from C++”

Actually took two years

Thinking in Python

Research mode now, web page with notes at www.BruceEckel.com

The other books and languages wrapped around me like Jacob Marley’s chains…

A ‘Bout’ of Perl

After C++ and Java, seemed amazing

Python is executable pseudocode. Perl is executable line noise.

Perl is like vice grips. You can do anything with it, and it's the wrong tool for every job

Leaves teeth marks everywhere

Perl is worse than Python because people wanted it worse. Larry Wall, 14 Oct 1998

I would actively encourage my competition to use Perl. Sean True, 30 Mar 1999

Top 10 Reasons Why I Love Python

10. Reduced Clutter

Programs are read more than they are written

XP: Consistent formatting really is important

Readability and compactness

Part of “conservation of complexity”

Consistent use of programming idioms improves understandability

Rapid understanding

The opposite of “more than one way to do it”

9. It’s not backward-compatible in exchange for pain

C++: Backward compatible with C – its strength and its bane

Java: more or less with C++ syntax (not too bad, but a lot of typing)

Perl: compatible with every hacky syntax of every Unix tool ever invented

C# and .NET: backward compatible with previous Microsoft marketing campaigns

Javascript: not even compatible with itself

8. It doesn’t value performance over my productivity

C++: can’t let go of C performance

Better than C, sure, but still takes forever to get something working; memory leaks are almost impossible to design out

Java: Primitive types require awkward coding (primitives “necessary” for speed)

As opposed to Python: everything is an object; escape mechanism (extension) for speed

7. It doesn’t treat me like I’m stupid

“Operator overloading is bad because you can make ugly code with it”

“finalize( ) does something”

“We reviewed Java designs before putting them into the language”

“Java has an open development process”

6. I don’t wait forever for a full implementation of the language

Some features we invented in the C++ committee are still not implemented

Unused features don’t get tested; circular problem

Many C++ vendors say “it’s hard, and no one’s asking for it.”

5. It doesn’t make assumptions about how we discover errors

Is strong static type checking really the only way to be sure?

Lack of good static typing in pre-ANSI C was certainly heaps of trouble

Doesn’t mean it’s the best solution

(More about this later)

Errors discovered with real data seem to me to be the hardest to find

4. Marketing people are not involved

“Java is flawless”

Microsoft “Visual” “C++”

Microsoft happens

Of course, Python isn’t immune

3. I don’t have to type so much

… And I don’t have to wade through so much code when I’m reading

Conservation of complexity: simplicity really does make a difference

But the right typing

Not obscure like APL

Not endlessly inventive like Perl or FORTH

2. My guesses are usually right

I still have to look up how to open a file every time I do it in Java

In fact, most things in Java require me to look something up

I can remember many Python idioms because they’re simpler

One more reason I program faster

1. Python lets me focus on concepts

No stumbling through Java designs, fighting with C++ compilations or run-time bugs.

Python and “The Tipping Point”

Email: possible to carry on dozens of conversations by paper mail, but you don’t.

Automating Everything:

Possible to write programs to automate every task. But you don’t.

Python makes it easy enough

Great with Gnu make (my CD build system)

Weak typing

Only constraints on an object that is passed into a function are that the function can apply its operations to that object

def sum(arg1, arg2): return arg1 + arg2 print sum(42, 47) print sum('spam', 'eggs')

“ Weak” sounds bad

Weak Typing in C++: Templates

#include <string>

#include <iostream>

using namespace std;

template<class A, class B, class R>

R sum(A a, B b) {

return a + b;

}

int main() {

string a("one"), b("two")

cout << sum<string, string, string>(a, b) << endl;

cout << sum<int, int, int>(1, 2) << endl;

}

Weak Typing in Java

Reflection, possibly with interfaces

interface addable { Object add(Object b);} class X implements addable { public Object add(Object b) { return new Object(); // Test } } class AddableNotFoundException extends Exception {} public class WeakTyping { public static Object sum(Object a, Object b) throws AddableNotFoundException { Class[] intfs = a.getClass().getInterfaces(); for(int i = 0; i < intfs.length; i++) if(intfs[i] == addable.class) return ((addable)a).add(b); throw new AddableNotFoundException(); } public static void main(String[] args) throws Exception { X a = new X(); X b = new X(); Object c = sum(a, b); } }

Why weak typing isn't weak