diff options
-rw-r--r-- | css.html.markdown | 6 | ||||
-rw-r--r-- | python3.html.markdown | 62 | ||||
-rw-r--r-- | ru-ru/ruby-ru.html.markdown | 1 |
3 files changed, 65 insertions, 4 deletions
diff --git a/css.html.markdown b/css.html.markdown index 7224d80a..e217906f 100644 --- a/css.html.markdown +++ b/css.html.markdown @@ -4,6 +4,7 @@ contributors: - ["Mohammad Valipour", "https://github.com/mvalipour"] - ["Marco Scannadinari", "https://github.com/marcoms"] - ["Geoffrey Liu", "https://github.com/g-liu"] + - ["Connor Shea", "https://github.com/connorshea"] filename: learncss.css --- @@ -238,10 +239,13 @@ of what you use in CSS with your target browsers. [QuirksMode CSS](http://www.quirksmode.org/css/) is one of the best sources for this. -To run a quick compatibility check, [CanIUse](http://caniuse.com) is a great resource. +To run a quick compatibility check, [Can I Use...](http://caniuse.com) is a great resource. ## Further Reading +* [Mozilla Developer Network's CSS documentation](https://developer.mozilla.org/en-US/docs/Web/CSS) +* [Codrops' CSS Reference](http://tympanus.net/codrops/css_reference/) * [Understanding Style Precedence in CSS: Specificity, Inheritance, and the Cascade](http://www.vanseodesign.com/css/css-specificity-inheritance-cascaade/) * [QuirksMode CSS](http://www.quirksmode.org/css/) * [Z-Index - The stacking context](https://developer.mozilla.org/en-US/docs/Web/Guide/CSS/Understanding_z_index/The_stacking_context) +* [SCSS](http://sass-lang.com/) and [LESS](http://lesscss.org/) for CSS pre-processing diff --git a/python3.html.markdown b/python3.html.markdown index b3acb122..971ca0a4 100644 --- a/python3.html.markdown +++ b/python3.html.markdown @@ -4,6 +4,7 @@ contributors: - ["Louie Dinh", "http://pythonpracticeprojects.com"] - ["Steven Basart", "http://github.com/xksteven"] - ["Andre Polykanine", "https://github.com/Oire"] + - ["Zachary Ferguson", "http://github.com/zfergus2"] filename: learnpython3.py --- @@ -36,7 +37,7 @@ Note: This article applies to Python 3 specifically. Check out [here](http://lea 8 - 1 # => 7 10 * 2 # => 20 -# Except division which returns floats by default +# Except division which returns floats, real numbers, by default 35 / 5 # => 7.0 # Result of integer division truncated down both for positive and negative. @@ -51,13 +52,13 @@ Note: This article applies to Python 3 specifically. Check out [here](http://lea # Modulo operation 7 % 3 # => 1 -# Exponentiation (x to the yth power) +# Exponentiation (x**y, x to the yth power) 2**4 # => 16 # Enforce precedence with parentheses (1 + 3) * 2 # => 8 -# Boolean values are primitives +# Boolean values are primitives (Note: the capitalization) True False @@ -95,6 +96,16 @@ False or True #=> True 1 < 2 < 3 # => True 2 < 3 < 2 # => False +# (is vs. ==) is checks if two variable refer to the same object, but == checks +# if the objects pointed to have the same values. +a = [1, 2, 3, 4] # Point a at a new list, [1, 2, 3, 4] +b = a # Point b at what a is pointing to +b is a # => True, a and b refer to the same object +b == a # => True, a's and b's objects are equal +b = [1, 2, 3, 4] # Point a at a new list, [1, 2, 3, 4] +b is a # => False, a and b do not refer to the same object +b == a # => True, a's and b's objects are equal + # Strings are created with " or ' "This is a string." 'This is also a string.' @@ -145,6 +156,10 @@ bool({}) #=> False # Python has a print function print("I'm Python. Nice to meet you!") +# By default the print function also prints out a newline at the end. +# Use the optional argument end to change the end character. +print("Hello, World", end="!") # => Hello, World! + # No need to declare variables before assigning to them. # Convention is to use lower_case_with_underscores some_var = 5 @@ -191,6 +206,9 @@ li[::-1] # => [3, 4, 2, 1] # Use any combination of these to make advanced slices # li[start:end:step] +# Make a one layer deep copy using slices +li2 = li[:] # => li2 = [1, 2, 4, 3] but (li2 is li) will result in false. + # Remove arbitrary elements from a list with "del" del li[2] # li is now [1, 2, 3] @@ -213,6 +231,12 @@ tup = (1, 2, 3) tup[0] # => 1 tup[0] = 3 # Raises a TypeError +# Note that a tuple of length one has to have a comma after the last element but +# tuples of other lengths, even zero, do not. +type((1)) # => <class 'int'> +type((1,)) # => <class 'tuple'> +type(()) # => <class 'tuple'> + # You can do most of the list operations on tuples too len(tup) # => 3 tup + (4, 5, 6) # => (1, 2, 3, 4, 5, 6) @@ -232,6 +256,12 @@ empty_dict = {} # Here is a prefilled dictionary filled_dict = {"one": 1, "two": 2, "three": 3} +# Note keys for dictionaries have to be immutable types. This is to ensure that +# the key can be converted to a constant hash value for quick look-ups. +# Immutable types include ints, floats, strings, tuples. +invalid_dict = {[1,2,3]: "123"} # => Raises a TypeError: unhashable type: 'list' +valid_dict = {(1,2,3):[1,2,3]} # Values can be of any type, however. + # Look up values with [] filled_dict["one"] # => 1 @@ -278,6 +308,10 @@ empty_set = set() # Initialize a set with a bunch of values. Yeah, it looks a bit like a dict. Sorry. some_set = {1, 1, 2, 2, 3, 4} # some_set is now {1, 2, 3, 4} +# Similar to keys of a dictionary, elements of a set have to be immutable. +invalid_set = {[1], 1} # => Raises a TypeError: unhashable type: 'list' +valid_set = {(1,), 1} + # Can set new variables to a set filled_set = some_set @@ -299,6 +333,7 @@ filled_set | other_set # => {1, 2, 3, 4, 5, 6} 10 in filled_set # => False + #################################################### ## 3. Control Flow and Iterables #################################################### @@ -352,6 +387,18 @@ for i in range(4, 8): print(i) """ +"range(lower, upper, step)" returns an iterable of numbers +from the lower number to the upper number, while incrementing +by step. If step is not indicated, the default value is 1. +prints: + 4 + 6 + 8 +""" +for i in range(4, 8, 2): + print(i) +""" + While loops go until a condition is no longer met. prints: 0 @@ -464,6 +511,15 @@ all_the_args(*args) # equivalent to foo(1, 2, 3, 4) all_the_args(**kwargs) # equivalent to foo(a=3, b=4) all_the_args(*args, **kwargs) # equivalent to foo(1, 2, 3, 4, a=3, b=4) +# Returning multiple values (with tuple assignments) +def swap(x, y): + return y, x # Return multiple values as a tuple without the parenthesis. + # (Note: parenthesis have been excluded but can be included) + +x = 1 +y = 2 +x, y = swap(x, y) # => x = 2, y = 1 +# (x, y) = swap(x,y) # Again parenthesis have been excluded but can be included. # Function Scope x = 5 diff --git a/ru-ru/ruby-ru.html.markdown b/ru-ru/ruby-ru.html.markdown index 318e0e09..69b5fb46 100644 --- a/ru-ru/ruby-ru.html.markdown +++ b/ru-ru/ruby-ru.html.markdown @@ -158,6 +158,7 @@ array << 6 #=> [1, 2, 3, 4, 5, 6] hash = {'color' => 'green', 'number' => 5} hash.keys #=> ['color', 'number'] +hash.values #=> ['green', 5] # Значение в хэше легко может быть найдено по ключу: hash['color'] #=> 'green' |