Question

What’s the equivalent of PHP’s “append to array” ($my_array[] = "abc";) in Python, which I have recently started learning?

Let’s say that I’ve a dictionary like this:

my_dict = {'fruits':['orange', 'pear']}

And now I want to add another fruit to my_dict['fruits']: apple

Answer 1

Python is great for experimenting and helping you find things like this, and as you already know roughly what you’re looking for (just named/termed differently), then here’s a tip that should make it a bit easier for you…

>>> my_dict = {'fruits':['orange', 'pear']}
>>> type(my_dict['fruits'])
<type 'list'>

So we know that it’s list (in this case the built-in list type)… We know we want to “add” something to it… So let’s look at what it offers…

>>> dir(list)
['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__delslice__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__getslice__', '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__iter__', '__le__', '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__reversed__', '__rmul__', '__setattr__', '__setitem__', '__setslice__', '__sizeof__', '__str__', '__subclasshook__', 'append', 'count', 'extend', 'index', 'insert', 'pop', 'remove', 'reverse', 'sort']

insert, extend and append look useful… Let’s see what it says…

>>> help(list.extend)
Help on method_descriptor:

extend(...)
    L.extend(iterable) -- extend list by appending elements from the iterable

Doesn’t sound quite right…

>>> help(list.insert)
Help on method_descriptor:

insert(...)
    L.insert(index, object) -- insert object before index

Seems a little specific about positioning…

>>> help(list.append)
Help on method_descriptor:

append(...)
    L.append(object) -- append object to end

Hey, looking good 🙂

It just so happens that in this instance, you could just do help(my_dict['fruits'])…