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(loop for i in '(one two three four five six) do (print i)) (loop for i in '(one two three four five six) by #'cddr do (print i)) ;prints ONE THREE FIVE (loop for i on '(a b c d e f g) do (print (length i))) ;prints 7 6 5 4 3 2 1 (loop for i on '(a b c d e f g) by #'cddr ...

(defvar *ht* (make-hash-table)) (loop for (sym num) on '(one 1 two 2 three 3 four 4 five 5 six 6 seven 7 eight 8 nine 9 ten 10) by #'cddr do (setf (gethash sym *ht*) num)) (loop for k being each hash-key of *ht* do (print k)) ; iterate over the keys (loop for k ...

(loop for s being the symbols in 'cl do (print s)) (loop for s being the present-symbols in :cl do (print s)) (loop for s being the external-symbols in (find-package "COMMON LISP") do (print s)) (loop for s being each external-symbols of "COMMON LISP" ...

The emptiness of a list is associated to the boolean False, so you don't have to check len(lst) == 0, but just lst or not lst lst = [] if not lst: print("list is empty") # Output: list is empty

This example assumes you have already installed Java and Gradle. Use the following project structure: src/ main/ java/ com/ example/ Application.java build.gradle build.gradle is your build script for Gradle build system with the following content: buildscri...

You can add items to a user's Reading List in Safari by calling the addItem method on the SSReadingList singleton. let readingList = SSReadingList.default() readingList?.addItem(with: yourURL, title: "optional title", previewText: "optional preview text") The default Reading...

The function map() from the package maps provides a simple starting point for creating maps with R. A basic world map can be drawn as follows: require(maps) map() The color of the outline can be changed by setting the color parameter, col, to either the character name or hex value of a color...

Considering the following dictionary: d = {"a": 1, "b": 2, "c": 3} To iterate through its keys, you can use: for key in d: print(key) Output: "a" "b" "c" This is equivalent to: for key in d.keys(): print(key) ...

Say you have a library website, and you want to have a custom post type named Books. It can be registered as function create_bookposttype() { $args = array( 'public' => true, 'labels' => array( 'name' => __( 'Books' ), 'singular_name' => ...

The following program says hello to the user. It takes one positional argument, the name of the user, and can also be told the greeting. import argparse parser = argparse.ArgumentParser() parser.add_argument('name', help='name of user' ) parser.add_argument('-g', '--greeting', ...

To join two or more path components together, firstly import os module of python and then use following: import os os.path.join('a', 'b', 'c') The advantage of using os.path is that it allows code to remain compatible over all operating systems, as this uses the separator appropriate for the pl...

Every package requires a setup.py file which describes the package. Consider the following directory structure for a simple package: +-- package_name | | | +-- __init__.py | +-- setup.py The __init__.py contains only the line def foo(): return 100. The following setup.py...

unique drops duplicates so that each element in the result is unique (only appears once): x = c(2, 1, 1, 2, 1) unique(x) # 2 1 Values are returned in the order they first appeared. duplicated tags each duplicated element: duplicated(x) # FALSE FALSE TRUE TRUE TRUE anyDuplicated(x) >...

To count how many elements of two sets overlap, one could write a custom function: xtab_set <- function(A, B){ both <- union(A, B) inA <- both %in% A inB <- both %in% B return(table(inA, inB)) } A = 1:20 B = 10:30 xtab_set(A, B) # inB ...

Imagine you have the following HTML: <div> <label>Name:</label> John Smith </div> And you need to locate the text "John Smith" after the label element. In this case, you can locate the label element by text and then use .next_sibling property: from ...

BeautifulSoup has a limited support for CSS selectors, but covers most commonly used ones. Use select() method to find multiple elements and select_one() to find a single element. Basic example: from bs4 import BeautifulSoup data = """ <ul> <li class="item&quo...

You can restrict the valid types used in a generic class by bounding that type in the class definition. Given the following simple type hierarchy: public abstract class Animal { public abstract String getSound(); } public class Cat extends Animal { public String getSound() { ...

Sometimes it's necessary to be able to extract values from an object using only references (ie. without transferring ownership). struct Token { pub id: u32 } struct User { pub token: Option<Token> } fn main() { // Create a user with an arbitrary token let user = User...

Let's say we have the following data: >>> data = {"cats": [{"name": "Tubbs", "color": "white"}, {"name": "Pepper", "color": "black"}]} Just dumping this as JSON does not do anything special here: ...

For if you have to fine-tune what is published. import { Mongo } from 'meteor/mongo'; import { Meteor } from 'meteor/meteor'; import { Random } from 'meteor/random'; if (Meteor.isClient) { // established this collection on the client only. // a name is required (first parameter) and this...