diff options
| -rw-r--r-- | ocaml.html.markdown | 10 | ||||
| -rw-r--r-- | python.html.markdown | 14 | ||||
| -rw-r--r-- | python3.html.markdown | 32 |
3 files changed, 44 insertions, 12 deletions
diff --git a/ocaml.html.markdown b/ocaml.html.markdown index fd7ca36e..c104823a 100644 --- a/ocaml.html.markdown +++ b/ocaml.html.markdown @@ -1,5 +1,5 @@ --- -language: "OCaml" +language: OCaml contributors: - ["Daniil Baturin", "http://baturin.org/"] --- @@ -20,6 +20,7 @@ source of confusion for beginners. When you are in the top level loop, OCaml will print the inferred type after you enter an expression. + ``` # let inc x = x + 1 ;; val inc : int -> int = <fun> @@ -42,6 +43,7 @@ val inc : int -> int val add : int -> int -> int val a : int ``` + Note that type signatures of functions of multiple arguments are written in curried form. @@ -304,6 +306,6 @@ sum_int_list t ;; ## Further reading -* Visit the official website to get the compiler and read the docs: http://ocaml.org/ -* Try interactive tutorials and a web-based interpreter by OCaml Pro: http://try.ocamlpro.com/ -* Read "OCaml for the skeptical" course: http://www2.lib.uchicago.edu/keith/ocaml-class/home.html +* Visit the official website to get the compiler and read the docs: <http://ocaml.org/> +* Try interactive tutorials and a web-based interpreter by OCaml Pro: <http://try.ocamlpro.com/> +* Read "OCaml for the skeptical" course: <http://www2.lib.uchicago.edu/keith/ocaml-class/home.html> diff --git a/python.html.markdown b/python.html.markdown index 9057dde2..390c7b76 100644 --- a/python.html.markdown +++ b/python.html.markdown @@ -57,9 +57,17 @@ to Python 2.x. Look for another tour of Python 3 soon! # Enforce precedence with parentheses (1 + 3) * 2 # => 8 -# Boolean values are primitives -True -False +# Boolean Operators ++# Note "and" and "or" are case-sensitive ++True and False #=> False ++False or True #=> True ++ ++# Note using Bool operators with ints ++0 and 2 #=> 0 ++-5 or 0 #=> -5 ++0 == False #=> True ++2 == True #=> False +1 == True #=> True # negate with not not True # => False diff --git a/python3.html.markdown b/python3.html.markdown index f6babaff..a94f4eae 100644 --- a/python3.html.markdown +++ b/python3.html.markdown @@ -61,6 +61,18 @@ False not True # => False not False # => True +# Boolean Operators +# Note "and" and "or" are case-sensitive +True and False #=> False +False or True #=> True + +# Note using Bool operators with ints +0 and 2 #=> 0 +-5 or 0 #=> -5 +0 == False #=> True +2 == True #=> False +1 == True #=> True + # Equality is == 1 == 1 # => True 2 == 1 # => False @@ -127,7 +139,8 @@ bool({}) #=> False # Python has a print function print("I'm Python. Nice to meet you!") -# No need to declare variables before assigning to them. Convention is to use lower_case_with_underscores +# No need to declare variables before assigning to them. +# Convention is to use lower_case_with_underscores some_var = 5 some_var # => 5 @@ -176,7 +189,8 @@ li[::-1] # => [3, 4, 2, 1] del li[2] # li is now [1, 2, 3] # You can add lists -li + other_li # => [1, 2, 3, 4, 5, 6] - Note: values for li and for other_li are not modified. +# Note: values for li and for other_li are not modified. +li + other_li # => [1, 2, 3, 4, 5, 6] # Concatenate lists with "extend()" li.extend(other_li) # Now li is [1, 2, 3, 4, 5, 6] @@ -215,14 +229,17 @@ filled_dict = {"one": 1, "two": 2, "three": 3} # Look up values with [] filled_dict["one"] # => 1 -# Get all keys as a list with "keys()". We need to wrap the call in list() because we are getting back an iterable. We'll talk about those later. -list(filled_dict.keys()) # => ["three", "two", "one"] +# Get all keys as a list with "keys()". +# We need to wrap the call in list() because we are getting back an iterable. We'll talk about those later. # Note - Dictionary key ordering is not guaranteed. # Your results might not match this exactly. +list(filled_dict.keys()) # => ["three", "two", "one"] + # Get all values as a list with "values()". Once again we need to wrap it in list() to get it out of the iterable. -list(filled_dict.values()) # => [3, 2, 1] # Note - Same as above regarding key ordering. +list(filled_dict.values()) # => [3, 2, 1] + # Check for existence of keys in a dictionary with "in" "one" in filled_dict # => True @@ -242,6 +259,10 @@ filled_dict.get("four", 4) # => 4 filled_dict.setdefault("five", 5) # filled_dict["five"] is set to 5 filled_dict.setdefault("five", 6) # filled_dict["five"] is still 5 +# Adding to a dictionary +filled_dict.update({"four":4}) #=> {"one": 1, "two": 2, "three": 3, "four": 4} +#filled_dict["four"] = 4 #another way to add to dict + # Remove keys from a dictionary with del del filled_dict["one"] # Removes the key "one" from filled dict @@ -458,6 +479,7 @@ map(add_10, [1, 2, 3]) # => [11, 12, 13] filter(lambda x: x > 5, [3, 4, 5, 6, 7]) # => [6, 7] # We can use list comprehensions for nice maps and filters +# List comprehension stores the output as a list which can itself be a nested list [add_10(i) for i in [1, 2, 3]] # => [11, 12, 13] [x for x in [3, 4, 5, 6, 7] if x > 5] # => [6, 7] |