Completeing List Equality and strings
This commit is contained in:
parent
d749795c31
commit
e4659b16b5
3 changed files with 46 additions and 46 deletions
|
|
@ -3,37 +3,37 @@
|
|||
|
||||
(meditations
|
||||
"We shall contemplate truth by testing reality, via equality"
|
||||
(= __ true)
|
||||
(= true true)
|
||||
|
||||
"To understand reality, we must compare our expectations against reality"
|
||||
(= __ (+ 1 1))
|
||||
(= 2 (+ 1 1))
|
||||
|
||||
"You can test equality of many things"
|
||||
(= (+ 3 4) 7 (+ 2 __))
|
||||
(= (+ 3 4) 7 (+ 2 5))
|
||||
|
||||
"Some things may appear different, but be the same"
|
||||
(= __ (= 2 2/1))
|
||||
(= true (= 2 2/1))
|
||||
|
||||
"You cannot generally float to heavens of integers"
|
||||
(= __ (= 2 2.0))
|
||||
(= false (= 2 2.0))
|
||||
|
||||
"But a looser equality is also possible"
|
||||
(= __ (== 2.0 2))
|
||||
(= true (== 2.0 2))
|
||||
|
||||
"Something is not equal to nothing"
|
||||
(= __ (not (= 1 nil)))
|
||||
(= true (not (= 1 nil)))
|
||||
|
||||
"Strings, and keywords, and symbols: oh my!"
|
||||
(= __ (= "hello" :hello 'hello))
|
||||
(= false (= "hello" :hello 'hello))
|
||||
|
||||
"Make a keyword with your keyboard"
|
||||
(= :hello (keyword __))
|
||||
(= :hello (keyword :hello))
|
||||
|
||||
"Symbolism is all around us"
|
||||
(= 'hello (symbol __))
|
||||
(= 'hello (symbol :hello))
|
||||
|
||||
"What could be equivalent to nothing?"
|
||||
(= __ nil)
|
||||
(= nil nil)
|
||||
|
||||
"When things cannot be equal, they must be different"
|
||||
(not= :fill-in-the-blank __))
|
||||
(not= :fill-in-the-blank true))
|
||||
|
|
|
|||
|
|
@ -4,67 +4,67 @@
|
|||
|
||||
(meditations
|
||||
"A string is nothing more than text surrounded by double quotes"
|
||||
(= __ "hello")
|
||||
(= "hello" "hello")
|
||||
|
||||
"But double quotes are just magic on top of something deeper"
|
||||
(= __ (str 'world))
|
||||
(= "world" (str 'world))
|
||||
|
||||
"You can do more than create strings, you can put them together"
|
||||
(= "Cool right?" (str __ __))
|
||||
(= "Cool right?" (str "Cool" " " "right?"))
|
||||
|
||||
"You can even get certain characters"
|
||||
(= \C (get "Characters" __))
|
||||
(= \C (get "Characters" 0))
|
||||
|
||||
"Or even count the characters"
|
||||
(= __ (count "Hello World"))
|
||||
(= 11 (count "Hello World"))
|
||||
|
||||
"But strings and characters are not the same"
|
||||
(= __ (= \c "c"))
|
||||
(= false (= \c "c"))
|
||||
|
||||
"What if you only wanted to get part of a string?"
|
||||
(= "World" (subs "Hello World" __ __))
|
||||
(= "World" (subs "Hello World" 6 11))
|
||||
|
||||
"How about joining together elements in a list?"
|
||||
(= __ (string/join '(1 2 3)))
|
||||
(= "123" (string/join '(1 2 3)))
|
||||
|
||||
"What if you wanted to separate them out?"
|
||||
(= "1, 2, 3" (string/join __ '(1 2 3)))
|
||||
(= "1, 2, 3" (string/join ", " '(1 2 3)))
|
||||
|
||||
"Maybe you want to separate out all your lines"
|
||||
(= [__ __ __] (string/split-lines "1\n2\n3"))
|
||||
(= ["1" "2" "3"] (string/split-lines "1\n2\n3"))
|
||||
|
||||
"You may want to make sure your words are backwards"
|
||||
(= __ (string/reverse "hello"))
|
||||
(= "olleh" (string/reverse "hello"))
|
||||
|
||||
"Maybe you want to find the index of the first occurrence of a substring"
|
||||
(= 0 (string/index-of "hello world" __))
|
||||
(= 0 (string/index-of "hello world" "h"))
|
||||
|
||||
"Or maybe the last index of the same"
|
||||
(= __ (string/last-index-of "hello world, hello" "hello"))
|
||||
(= 13 (string/last-index-of "hello world, hello" "hello"))
|
||||
|
||||
"But when something doesn't exist, nothing is found"
|
||||
(= __ (string/index-of "hello world" "bob"))
|
||||
(= nil (string/index-of "hello world" "bob"))
|
||||
|
||||
"Sometimes you don't want whitespace cluttering the front and back"
|
||||
(= __ (string/trim " \nhello world \t \n"))
|
||||
(= "hello world" (string/trim " \nhello world \t \n"))
|
||||
|
||||
"You can check if something is a char"
|
||||
(= __ (char? \c))
|
||||
(= true (char? \c))
|
||||
|
||||
"But it may not be"
|
||||
(= __ (char? "a"))
|
||||
(= false (char? "a"))
|
||||
|
||||
"But chars aren't strings"
|
||||
(= __ (string? \b))
|
||||
(= false (string? \b))
|
||||
|
||||
"Strings are strings"
|
||||
(= true (string? __))
|
||||
(= true (string? "a"))
|
||||
|
||||
"Some strings may be blank"
|
||||
(= __ (string/blank? ""))
|
||||
(= true (string/blank? ""))
|
||||
|
||||
"Even if at first glance they aren't"
|
||||
(= __ (string/blank? " \n \t "))
|
||||
(= true (string/blank? " \n \t "))
|
||||
|
||||
"However, most strings aren't blank"
|
||||
(= __ (string/blank? "hello?\nare you out there?")))
|
||||
(= false (string/blank? "hello?\nare you out there?")))
|
||||
|
|
|
|||
|
|
@ -3,43 +3,43 @@
|
|||
|
||||
(meditations
|
||||
"Lists can be expressed by function or a quoted form"
|
||||
(= '(__ __ __ __ __) (list 1 2 3 4 5))
|
||||
(= '(1 2 3 4 5) (list 1 2 3 4 5))
|
||||
|
||||
"They are Clojure seqs (sequences), so they allow access to the first"
|
||||
(= __ (first '(1 2 3 4 5)))
|
||||
(= 1 (first '(1 2 3 4 5)))
|
||||
|
||||
"As well as the rest"
|
||||
(= __ (rest '(1 2 3 4 5)))
|
||||
(= '(2 3 4 5) (rest '(1 2 3 4 5)))
|
||||
|
||||
"Count your blessings"
|
||||
(= __ (count '(dracula dooku chocula)))
|
||||
(= 3 (count '(dracula dooku chocula)))
|
||||
|
||||
"Before they are gone"
|
||||
(= __ (count '()))
|
||||
(= 0 (count '()))
|
||||
|
||||
"The rest, when nothing is left, is empty"
|
||||
(= __ (rest '(100)))
|
||||
(= () (rest '(100)))
|
||||
|
||||
"Construction by adding an element to the front is easy"
|
||||
(= __ (cons :a '(:b :c :d :e)))
|
||||
(= '(:a :b :c :d :e) (cons :a '(:b :c :d :e)))
|
||||
|
||||
"Conjoining an element to a list isn't hard either"
|
||||
(= __ (conj '(:a :b :c :d) :e))
|
||||
(= '(:e :a :b :c :d) (conj '(:a :b :c :d) :e))
|
||||
|
||||
"You can use a list like a stack to get the first element"
|
||||
(= __ (peek '(:a :b :c :d :e)))
|
||||
(= :a (peek '(:a :b :c :d :e)))
|
||||
|
||||
"Or the others"
|
||||
(= __ (pop '(:a :b :c :d :e)))
|
||||
(= '(:b :c :d :e) (pop '(:a :b :c :d :e)))
|
||||
|
||||
"But watch out if you try to pop nothing"
|
||||
(= __ (try
|
||||
(= "No dice!" (try
|
||||
(pop '())
|
||||
(catch IllegalStateException e
|
||||
"No dice!")))
|
||||
|
||||
"The rest of nothing isn't so strict"
|
||||
(= __ (try
|
||||
(= () (try
|
||||
(rest '())
|
||||
(catch IllegalStateException e
|
||||
"No dice!"))))
|
||||
|
|
|
|||
Loading…
Reference in a new issue