@kwugirl Wow Code, Such Read! KWu Ruby Agent Engineer amaze understand so power 

@kwugirl the goal: get better at reading code 

be fearless in diving into code you don’t know Edmond Lau theeffectiveengineer.com 

@kwugirl 

@kwugirl 10.000 hours 

@kwugirl 10.000 hours 250 weeks 

@kwugirl 10.000 hours 250 weeks ~5 years! 

@kwugirl productive struggling 

@kwugirl code archaeology https://www.flickr.com/photos/22134952@N04/2850397739 

@kwugirl 2. remember your question 3. enlist help 1. see the code 

@kwugirl the problem 

@kwugirl the problem connection.execute("EXPLAIN #{query}") 

@kwugirl the problem connection.execute("EXPLAIN #{query}") SELECT "blogs".* FROM "blogs" WHERE "blogs"."id" = $1 LIMIT 1 with 

@kwugirl the problem connection.execute("EXPLAIN #{query}") SELECT "blogs".* FROM "blogs" WHERE "blogs"."id" = $1 LIMIT 1 with 

@kwugirl { :sql=>
 "SELECT \"blogs\".* FROM \"blogs\" WHERE \"blogs\".\"id \" = $1 LIMIT 1", … :binds=> [[#,…,42]] } ActiveSupport::Notifications.subscribe 'sql.active_record' 

@kwugirl { :sql=>
 "SELECT \"blogs\".* FROM \"blogs\" WHERE \"blogs\".\"id \" = $1 LIMIT 1", … :binds=> [[#,…,42]] } ActiveSupport::Notifications.subscribe 'sql.active_record' 

@kwugirl 2. remember your question 3. enlist help 1. see the code 

@kwugirl 

@kwugirl $ cd src/ 

@kwugirl $ cd src/ $ git clone [email protected]:rails/rails.git
 $ cd rails/ 

@kwugirl $ cd src/ $ git clone [email protected]:rails/rails.git
 $ cd rails/ $ git checkout v4.2.0 

@kwugirl # Gemfile gem 'rails', '4.2.0' 

@kwugirl # Gemfile # gem 'rails', '4.2.0' gem 'rails', :path => '../../src/rails' 

@kwugirl @instrumenter.instrument( "sql.active_record", :sql => sql, :name => name, :connection_id => object_id, :statement_name => statement_name, :binds => binds) { yield } def log(sql, name = "SQL", binds = [], statement_name = nil) # active_record/connection_adapters/abstract_adapter.rb 

@kwugirl @instrumenter.instrument( "sql.active_record", :sql => sql, :name => name, :connection_id => object_id, :statement_name => statement_name, :binds => binds) { yield } def log(sql, name = "SQL", binds = [], statement_name = nil) # active_record/connection_adapters/abstract_adapter.rb 

@kwugirl @instrumenter.instrument( "sql.active_record", :sql => sql, :name => name, :connection_id => object_id, :statement_name => statement_name, :binds => binds) { yield } def log(sql, name = "SQL", binds = [], statement_name = nil) # active_record/connection_adapters/abstract_adapter.rb 

@kwugirl def log(sql, name = "SQL", binds = [], statement_name = nil) @instrumenter.instrument( "sql.active_record", :sql => sql, :name => name, :connection_id => object_id, :statement_name => statement_name, :binds => binds) { yield } puts "====== HELLO IS IT ME YOU'RE LOOKING FOR?!!?? ======" # active_record/connection_adapters/abstract_adapter.rb 

@kwugirl git blame (can be) your friend 

@kwugirl 2. remember your question 3. enlist help 1. see the code 

@kwugirl don’t get lost 

@kwugirl don’t get lost learn one thing at a time 

@kwugirl don’t get lost learn one thing at a time what are your unknowns? 

@kwugirl the problem connection.execute("EXPLAIN #{query}") SELECT "blogs".* FROM "blogs" WHERE "blogs"."id" = $1 LIMIT 1 with 

@kwugirl the problem connection.execute("EXPLAIN #{query}") SELECT "blogs".* FROM "blogs" WHERE "blogs"."id" = $1 LIMIT 1 with 

@kwugirl the problem connection.execute("EXPLAIN #{query}") SELECT "blogs".* FROM "blogs" WHERE "blogs"."id" = $1 LIMIT 1 with 

@kwugirl 2. remember your question 3. enlist help 1. see the code 

@kwugirl pair programming 

@kwugirl pair programming ¿?¿?¿?¿?¿? ¿?¿?¿?¿?¿? ¿?¿?¿?¿?¿? 

@kwugirl 

@kwugirl What are you looking for? 

@kwugirl What are you looking for? Why? 

@kwugirl What are you looking for? Why? How did you know to look there? 

@kwugirl Kernel#caller 

@kwugirl active_record/connection_adapters/postgresql_adapter.rb:601:in `exec_cache' active_record/connection_adapters/postgresql_adapter.rb:585:in `execute_and_clear' active_record/connection_adapters/postgresql/database_statements.rb:161:in `exec_query' active_record/connection_adapters/abstract/database_statements.rb:341:in `select' active_record/connection_adapters/abstract/database_statements.rb:37:in `select_all' active_record/connection_adapters/abstract/query_cache.rb:70:in `select_all' active_record/querying.rb:39:in `find_by_sql' active_record/relation.rb:639:in `exec_queries' active_record/relation.rb:514:in `load' active_record/relation.rb:243:in `to_a' active_record/relation.rb:617:in `pretty_print' Kernel#caller 

@kwugirl Method#source_location 

@kwugirl Method#source_location $ bundle exec rails console 

@kwugirl Method#source_location $ bundle exec rails console irb(main):001:0> method(:try).source_location 

@kwugirl Method#source_location $ bundle exec rails console irb(main):001:0> method(:try).source_location => ["/…/active_support/core_ext/object/try.rb", 62] 

@kwugirl method_defined? RubyTapas #439 “Method Search” 

@kwugirl method_defined? $ ObjectSpace.each_object(Class).select{|c| c.singleton_class.method_defined?(:try_convert) } => [File, IO, Regexp, Hash, Array, String] RubyTapas #439 “Method Search” 

@kwugirl method_defined? $ ObjectSpace.each_object(Class).select{|c| c.singleton_class.method_defined?(:try_convert) } => [File, IO, Regexp, Hash, Array, String] RubyTapas #439 “Method Search” 

@kwugirl method_defined? $ ObjectSpace.each_object(Class).select{|c| c.singleton_class.method_defined?(:try_convert) } => [File, IO, Regexp, Hash, Array, String] RubyTapas #439 “Method Search” 

@kwugirl method_defined? $ ObjectSpace.each_object(Class).select{|c| c.singleton_class.method_defined?(:try_convert) } => [File, IO, Regexp, Hash, Array, String] RubyTapas #439 “Method Search” 

@kwugirl method_defined? $ ObjectSpace.each_object(Class).select{|c| c.singleton_class.method_defined?(:try_convert) } => [File, IO, Regexp, Hash, Array, String] RubyTapas #439 “Method Search” 

@kwugirl the solution connection.exec_query("EXPLAIN #{statement.sql}", "Explain #{statement.name}", statement.binds) wow beauty wonder 

@kwugirl the solution connection.exec_query("EXPLAIN #{statement.sql}", "Explain #{statement.name}", statement.binds) wow beauty wonder 

@kwugirl the solution connection.exec_query("EXPLAIN #{statement.sql}", "Explain #{statement.name}", statement.binds) wow beauty wonder 

@kwugirl success!!1!one!! 

@kwugirl success!!1!one!! $1 

@kwugirl success!!1!one!! $1 }Explain plan 

@kwugirl success!!1!one!! released in 3.15.2 $1 }Explain plan 

@kwugirl 2. remember your question 3. enlist help 1. see the code 

@kwugirl reading ruby source 

@kwugirl gentle intro 

@kwugirl gentle intro 

@kwugirl which files? 

@kwugirl which files? 

@kwugirl github.com/ruby/ruby 

@kwugirl github.com/ruby/ruby “trunk” not “master” 

@kwugirl pretty flat directory 

@kwugirl pretty flat directory 

@kwugirl std library in lib/ 

@kwugirl extension.rdoc 

@kwugirl parse.y 

@kwugirl other helpful points 

@kwugirl other helpful points rb_ 

@kwugirl other helpful points rb_ regex search with ^ to find method definition 

@kwugirl other helpful points rb_ regex search with ^ to find method definition comments 

@kwugirl bugs.ruby-lang.org 

@kwugirl resources 

@kwugirl resources readingcodegood.com 

@kwugirl resources readingcodegood.com schneems' talk “Dissecting Ruby with Ruby” 

@kwugirl resources readingcodegood.com schneems' talk “Dissecting Ruby with Ruby” schneems.com/2016/01/25/ruby-debugging-magic- cheat-sheet.html
 tenderlovemaking.com/2016/02/05/i-am-a-puts- debuggerer.html 

@kwugirl resources 

@kwugirl resources Jason Clark’s talk “GDB: A Gentle Intro” 

@kwugirl resources Jason Clark’s talk “GDB: A Gentle Intro” Hsing-Hui Hsu’s talk “Time flies like an arrow, fruit flies like a banana” 

@kwugirl resources Jason Clark’s talk “GDB: A Gentle Intro” Hsing-Hui Hsu’s talk “Time flies like an arrow, fruit flies like a banana” Ruby Under A Microscope 

@kwugirl resources Jason Clark’s talk “GDB: A Gentle Intro” Hsing-Hui Hsu’s talk “Time flies like an arrow, fruit flies like a banana” Ruby Under A Microscope Definitive Guide to Ruby’s C API: 
 https://silverhammermba.github.io/emberb/c/ 

@kwugirl Julia Evans jvns.ca 

@kwugirl Net::HTTP is maybe 2000 lines of code, not including comments. Julia Evans jvns.ca 

@kwugirl Net::HTTP is maybe 2000 lines of code, not including comments. It has ~1000 lines of comments… Julia Evans jvns.ca 

@kwugirl Net::HTTP is maybe 2000 lines of code, not including comments. It has ~1000 lines of comments… I can read 2000 lines of code, Julia Evans jvns.ca 

@kwugirl Net::HTTP is maybe 2000 lines of code, not including comments. It has ~1000 lines of comments… I can read 2000 lines of code, mostly! Julia Evans jvns.ca 

@kwugirl ¿?s 

@kwugirl appendix 

@kwugirl doge The White Rabbit, Alice in Wonderland sad Keanu pear/pair programming Lionel Richie + Where’s Waldo !!1!one!! the “!1” phenomenon breadfish Slurms MacKenzie, Futurama 

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