Regex Intro
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The document introduces regular expressions (regex), including what they are used for, basic syntax, and examples. It covers matching characters, character classes, quantifiers, alternation, and other regex topics in a tutorial-style format with explanations and practice examples.
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![^[Rr]egular [Ee]xpressions$ Introduction](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-1-320.jpg)
![Regular Expressions Composed of two types of characters Metacharacters / Special characters * ? ^ $ . [ ] Literal characters a b c d](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-3-320.jpg)
![Character Classes [ ] Matches one of the characters in the [ ] [ae] Matches ‘a’ or ‘e’ [aeiouy] Matches any vowel ^gr[ae]y$ Start of line followed by ‘g’ then ‘r’ then ‘a’ or ‘e’ then ‘y’ followed by end of line grey or gray](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-9-320.jpg)
![Character Classes cont. [Ss] Matches upper or lower case ‘S’ [123456] Matches any of the digits listed [Hh][123456] Matches H1, h2, h3, H4, etc](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-10-320.jpg)
![Special characters in [ ]’s - (dash) references a range [1-6] is the same as [123456] [a-f] is the same as [abcdef] Ranges can be mixed with literals [0-9a-fA-F_!.?] Any digit, upper or lower case ‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, underscore, exclamation, period or question mark](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-11-320.jpg)
![Negated character class [^ ] ^ inside of [ ] means “not any of these” [^1-6] Any character other than 1, 2, 3, 4, 5, 6 [^a-fA-F] Any character other than A-F (upper or lower) The ^ must be the first character inside [ ] [^c] (Matches anything but ‘c’) [c^] (Matches a ‘c’ or ‘^’)](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-12-320.jpg)
![Translating regex practice List of words that have ‘q’ followed by a character other than ‘u’ q[^u] List of words with ‘f’ followed by an ‘i’ or ‘o’ followed by ‘r’ then ‘e’ f[io]re Line starts with ‘Qu’ or ‘qu’ followed by an ‘e’ followed by any letter between ‘p’ and ‘t’ ^[Qq]ue[p-t]](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-13-320.jpg)
![Metacharacter: . (dot) Matches any character c.t ‘ c’ followed by any character followed by ‘t’ cat cot c8t Period inside of [ ]’s matches a period [a.c] Matches ‘a’, ‘.’ or ‘c’](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-14-320.jpg)
![Alternatives: | (pipe) Pipes allow you to specify alternatives grey|gray Matches on grey or gray Use parentheses to constrain alternatives gr(e|a)y Within [ ]’s, | is a normal character [a|b] Matches ‘a’ or ‘|’ or ‘b’](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-16-320.jpg)
![Regex practice Match “First Street” or “1st street” (First|1st) [Ss]treet (Fir|1)st [Ss]treet These are equivalent, which is better? Match “toothbrush” or “hairbrush” (tooth|hair)brush](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-18-320.jpg)
![Case insensitive match Matches are case sensitive by default [Ff]rom will match From but not FRom Use egrep’s -i option to do a case insensitive match Most languages have a case insensitive match as well](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-20-320.jpg)
![Quantifiers: + and * + (plus) One or more of the previous item * (star) Zero or more of the previous item b[0-9]*a ba b9999a b999999999999999a](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-22-320.jpg)
![More practice Match chat, cat, chart ch?ar?t c[h]?a[r]?t Start of line then M then one or more ‘a’ followed by ‘st’ and zero or more ‘b’ ^M[a]+st[b]* Lines ending with one or more ‘c’ followed by a ‘t’ then zero or one ‘e’ [c]+t[e]*$](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-25-320.jpg)
![More practice ^[Mm][^a-np-z]ney$ Start of line then ‘M’ or ‘m’ then any character not a-n and p-z then ‘ney’ followed by end of line Money, money, m3ney ^be.*(bob|ted)$ Start of line followed by ‘be’ followed by zero or more characters followed by ‘bob’ or ‘ted’ followed by end of line](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-26-320.jpg)
![More practice Match truck, firetruck but not dumptruck ^(fire)?truck$ $0.99, $599.95, $1000.45, $5000 \$[0-9]+(\.[0-9][0-9])?$ 404-555-1212, 404.555.1212, (404) 555-1212 ^[()0-9]+.[0-9]+.[0-9]+$](https://image.slidesharecdn.com/regex-intro-091117114736-phpapp01/85/Regex-Intro-27-320.jpg)
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Davinci git brown_bagJason Noble This document provides an overview of revision control systems like Git and GitHub. It discusses what revision control is, some early systems like SCCS and RCS, and then focuses on more modern distributed systems like SVN, Git, and Mercurial. For Git specifically, it covers features like non-linear development, easy branching and merging, auditing of history, and distributed development. It provides instructions for getting started with Git locally and also hosting projects on GitHub. Finally it advertises an additional hands-on training session for working through more examples.
Rspec 101
Rspec 101Jason Noble RSpec 101 provides an overview of RSpec and its main concepts:
1. describe() and it() are used to define example groups and examples (tests) within those groups. describe blocks can be nested and context() is an alias for describe().
2. before(), after(), around() hooks allow setting up and tearing down test environment/state. before(:each) runs before each example while before(:all) runs once for the group.
3. expect() is used to set expectations for what should happen rather than assertions for what will. Matchers like .equal(), .include() check expectations.
4. Helper methods, shared examples, and mocks can be used to DRY up
Dash of ajax
Dash of ajaxJason Noble This document discusses adding Ajax functionality to a shopping cart application. It describes using partial templates to render cart items, modifying the "Add to Cart" button to use Ajax, highlighting updated items, and hiding the empty cart. Tests are written to verify the Ajax actions. Homework includes making other interactions like adding from the product image or removing items use Ajax as well.
jQuery Intro
jQuery IntroJason Noble The document provides an overview of jQuery, a popular JavaScript library, including its history and benefits such as easy DOM manipulation, AJAX capabilities, and cross-browser compatibility. It then demonstrates several jQuery functions and selectors for modifying HTML elements, handling events, and making AJAX requests to update content without page refreshes. Examples are given for selecting elements, updating styles, handling events like clicks, and validating form input with plugins.
Intro to Rails Give Camp Atlanta
Intro to Rails Give Camp AtlantaJason Noble This document provides an introduction and overview of Ruby on Rails, including: its history and initial release in 2004; the Model-View-Controller architecture and included components; installing and setting up a basic Rails application; scaffolding a product catalog with CRUD functionality; adding validation, testing, and pushing the application to Heroku for deployment. It then demonstrates expanding the application by adding a shopping cart and checkout functionality using additional scaffolds, models, and controllers.
Google apps
Google appsJason Noble This document summarizes Google Apps, a free suite of business productivity applications from Google including Gmail, Google Calendar, Google Docs, and Google Sites. It provides an overview of the free and paid versions of Google Apps and guides users through the setup process, which involves signing up with a custom domain name and creating administrator and user accounts. Instructions are included for sharing calendars between users and embedding public calendars on websites.
Smarter cart
Smarter cartJason Noble This document discusses improvements made to an online shopping cart application in Rails. It covers adding a quantity column to line items with a default of 1, updating models and controllers to handle quantities, fixing duplicates in existing carts through a migration, using flash messages to notify users, and styling the cart view with CSS. Future tasks proposed are storing product price in line items, adding tests for unique and duplicate adds, improving flash messages, and enabling deletion or decrement of individual line items.
Cart creation-101217222728-phpapp01
Cart creation-101217222728-phpapp01Jason Noble This document summarizes steps for creating a shopping cart in a Rails application. It covers generating a Cart model and LineItem model with relationships, using Rails sessions to associate the cart with each user, adding public and private methods, callbacks and validations, adding a button to add items to the cart, and modifying views and controllers. Testing is done to ensure functionality. Homework includes enhancing the functionality by adding a click handler, session counter, and conditional display.
Catalog display
Catalog displayJason Noble The document discusses setting up a basic online store application in Rails. It covers generating a Store controller, routing requests to the store index action, displaying a list of products from the database, adding styles with CSS, using Rails helpers like number_to_currency to format prices, and writing functional tests for the controller. Homework includes adding a date to the sidebar, experimenting with number formatting options, and writing tests for the products controller.
Validation unit testing
Validation unit testingJason Noble This document discusses validation and unit testing in Ruby on Rails. It provides examples of:
1. Validating that text fields are not empty, price is greater than $0.01, title is unique, and image URL format is valid on the Product model.
2. Running model unit tests to validate the product attributes and specific validations like price being positive.
3. Using test fixtures to populate the test database with sample data and test assumptions by ensuring tests fail when validations are removed.
Creating the application
Creating the applicationJason Noble The document outlines the steps to create a Rails application called Depot that includes a Product model with title, description, image_url, and price attributes. It describes generating a scaffold for the Product model, running migrations to set up the database table, seeding the database with sample data, and pushing the application to Heroku. Key steps include generating the Rails application, adding the Product model, configuring the database, and deploying the application.
Capistrano
CapistranoJason Noble This document provides instructions for deploying a Rails application using Capistrano. It includes steps to set up Capistrano, configure the deploy.rb file, generate SSH keys, add the deploy key to GitHub, run Capistrano tasks to deploy the application, and make subsequent deploys when code changes. The application is deployed to a server at 192.168.255.54 running Mongrel and uses Git for version control.
Atlanta Pm Git 101
Atlanta Pm Git 101Jason Noble - Git is a distributed revision control system that keeps track of changes made to files over time through log messages and allows developers to easily share changes.
- Git has a basic workflow of modifying files, staging files, and committing files to the local repository.
- GitHub is a hosting service for Git repositories that allows collaboration on projects by multiple developers through pushing and pulling changes from a shared remote repository.
Git101
Git101Jason Noble The document provides an introduction to Git, a distributed revision control system, detailing its basic functionalities such as tracking changes, managing files, and collaborating with remote repositories on GitHub. It outlines the steps for setting up Git, including configuring user settings and establishing SSH keys, as well as a typical workflow for initiating, modifying, and pushing updates to a repository. Further, it discusses managing multiple committers and highlights processes for pulling updates from remote repositories.
Git Atlrug
Git AtlrugJason Noble The document outlines the process of using Git with remote repositories on GitHub, detailing steps for single and multiple committers. Key operations include making changes, staging, committing, pushing, pulling, and forking repositories. It explains the setup of public and private repositories, managing remote connections, and the creation of pull requests for collaboration.
Git102
Git102Jason Noble The document discusses the process of forking a GitHub repository, cloning it locally, making changes, and pushing those changes back to GitHub. It explains how to fork a repository to copy it to your GitHub account, then clone the fork locally and commit/push changes. It also covers adding the original repository as an "upstream" remote to pull updates from the source.
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- 2. Vocabulary Regular expression / Regex / Regexp Regex is pronounced Reg (as in register) Ex (as in FedEx) Matching Regex matches a string means it matches in a string
- 3. Regular Expressions Composed of two types of characters Metacharacters / Special characters * ? ^ $ . [ ] Literal characters a b c d
- 4. Egrep tool Allows you to use Regular Expressions to find words that match Available for Macs, PCs and Linux cat /usr/share/dict/words | egrep ‘…’ See http://regex.info/egrep.html if you don’t have it preinstalled
- 5. My first regex cat /usr/share/dict/words | egrep ‘cat’ Matches any words with a ‘c’ followed by an ‘a’ followed by a ‘t’ bobcat cat catwalk scatter Simple regex, only uses Literal chars
- 6. Metacharacters: ^ and $ ^ matches the beginning of a line $ matches the end of a line ^cat (start of line followed by ‘c’ then ‘a’ then ‘t’) cat catwalk cat$ (‘c’ followed by ‘a’ then ‘t’ followed by EOL) bobcat cat ^cat$ (start of line followed by ‘c’ then ‘a’ then ‘t’ then EOL) cat
- 7. How to read regex Read each character one at a time ^bat Start of line followed by ‘b’ then ‘a’ then ‘t’ rat$ ‘ r’ then ‘a’ then ‘t’ followed by end of line ^dog$ Start of line followed by ‘d’ then ‘o’ then ‘g’ then EOL
- 8. More simple regex’s ^ Start of line ^$ Start of line followed by end of line $ End of line ^foot$ Start of line followed by ‘f’ then ‘o’ then ‘o’ then ‘t’ followed by EOL
- 9. Character Classes [ ] Matches one of the characters in the [ ] [ae] Matches ‘a’ or ‘e’ [aeiouy] Matches any vowel ^gr[ae]y$ Start of line followed by ‘g’ then ‘r’ then ‘a’ or ‘e’ then ‘y’ followed by end of line grey or gray
- 10. Character Classes cont. [Ss] Matches upper or lower case ‘S’ [123456] Matches any of the digits listed [Hh][123456] Matches H1, h2, h3, H4, etc
- 11. Special characters in [ ]’s - (dash) references a range [1-6] is the same as [123456] [a-f] is the same as [abcdef] Ranges can be mixed with literals [0-9a-fA-F_!.?] Any digit, upper or lower case ‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, underscore, exclamation, period or question mark
- 12. Negated character class [^ ] ^ inside of [ ] means “not any of these” [^1-6] Any character other than 1, 2, 3, 4, 5, 6 [^a-fA-F] Any character other than A-F (upper or lower) The ^ must be the first character inside [ ] [^c] (Matches anything but ‘c’) [c^] (Matches a ‘c’ or ‘^’)
- 13. Translating regex practice List of words that have ‘q’ followed by a character other than ‘u’ q[^u] List of words with ‘f’ followed by an ‘i’ or ‘o’ followed by ‘r’ then ‘e’ f[io]re Line starts with ‘Qu’ or ‘qu’ followed by an ‘e’ followed by any letter between ‘p’ and ‘t’ ^[Qq]ue[p-t]
- 14. Metacharacter: . (dot) Matches any character c.t ‘ c’ followed by any character followed by ‘t’ cat cot c8t Period inside of [ ]’s matches a period [a.c] Matches ‘a’, ‘.’ or ‘c’
- 15. Periods cont. 03.19.76 Matches ‘03’ followed by a char then ‘19’ then any char then ‘76’ 03-19-76 03/19/76 03.19.76 03 19 76 03 3 19 8 76
- 16. Alternatives: | (pipe) Pipes allow you to specify alternatives grey|gray Matches on grey or gray Use parentheses to constrain alternatives gr(e|a)y Within [ ]’s, | is a normal character [a|b] Matches ‘a’ or ‘|’ or ‘b’
- 17. Pipes (cont.) Use parenthesis to constrain gre|ay matches ‘gre’ or ‘ay’ gr(e|a)y matches ‘gr’ followed by ‘e’ or ‘a’ then ‘y’
- 18. Regex practice Match “First Street” or “1st street” (First|1st) [Ss]treet (Fir|1)st [Ss]treet These are equivalent, which is better? Match “toothbrush” or “hairbrush” (tooth|hair)brush
- 19. ^ or $ and alternation Be careful when using ^ or $ with alternation ^From|Subject|Date: Start of line followed by From OR Subject OR Date: ^(From|Subject|Date): Start of line followed by ‘From’ or ‘Subject’ or ‘Date’ followed by ‘:’ Safer to use ()’s to group your alternates
- 20. Case insensitive match Matches are case sensitive by default [Ff]rom will match From but not FRom Use egrep’s -i option to do a case insensitive match Most languages have a case insensitive match as well
- 21. Quantifiers: ? ? metacharacter means optional colou?r matches color or colour ‘ c’ then ‘o’ then ‘l’ then ‘o’ then optionally ‘u’ then ‘r’ Match July or Jul and fourth, 4th and 4 (July|Jul) (fourth|4th|4) July? (fourth|4th|4) July? (fourth|4(th)?)
- 22. Quantifiers: + and * + (plus) One or more of the previous item * (star) Zero or more of the previous item b[0-9]*a ba b9999a b999999999999999a
- 23. Summary of Quantifiers Minimum Required Maximum to try Meaning ? none 1 zero or one occurrence * none no limit zero or more occurrences + 1 no limit one or more occurrences
- 24. Escaping metacharacters Use \ (backslash) to escape metacharacters \. matches ‘.’ . matches any character c.t matches cat c\.t does not match cat \(cat\) matches ‘(cat)’ not ‘cat’
- 25. More practice Match chat, cat, chart ch?ar?t c[h]?a[r]?t Start of line then M then one or more ‘a’ followed by ‘st’ and zero or more ‘b’ ^M[a]+st[b]* Lines ending with one or more ‘c’ followed by a ‘t’ then zero or one ‘e’ [c]+t[e]*$
- 26. More practice ^[Mm][^a-np-z]ney$ Start of line then ‘M’ or ‘m’ then any character not a-n and p-z then ‘ney’ followed by end of line Money, money, m3ney ^be.*(bob|ted)$ Start of line followed by ‘be’ followed by zero or more characters followed by ‘bob’ or ‘ted’ followed by end of line
- 27. More practice Match truck, firetruck but not dumptruck ^(fire)?truck$ $0.99, $599.95, $1000.45, $5000 \$[0-9]+(\.[0-9][0-9])?$ 404-555-1212, 404.555.1212, (404) 555-1212 ^[()0-9]+.[0-9]+.[0-9]+$