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My talk is scheduled for six minutes, so while you're waiting, you can try running my code snippet without executing it.
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Are you ready to try? Great! Let's go.
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My concern today is that I have a sore throat, and when I practiced, it took about 17 minutes.
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I need to deliver the talk at a slower pace, but I'll do my best.
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So, I have a question: how many of you here have never used a local variable before?
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Raise your hand if you have never used a local variable.
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Okay, it seems that everyone has used local variables.
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Now, another question: do you fully understand local variables?
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If you completely understand local variables, that’s great.
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Here's a simple demonstration: Ruby allows you to write this kind of code.
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This is just five lines of Ruby code. Technically, two lines should be hidden for better complexity.
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What do you think the answer is? Just shout it out if you know.
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Does anybody want to take a guess?
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You're correct! Even with a warning, Ruby handles it.
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This code captures a continuation and returns a string.
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In this case, it returns a string with multiple values.
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Let's play around with local variables in theory; this was my talk.
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The abstract for my presentation, published on the RubyKaigi website, states that this presentation will occur mostly in Vim.
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That helps me work quickly, allowing me to demonstrate code snippets effectively.
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I'm currently using this empty buffer; watch as I type Ruby code and trigger it.
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I assign this to be a variable, and then I run commands.
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The process runs smoothly.
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Hello everyone, my name is Tatsuhiro Ujihisa.
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You can call me Woody.
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I'm here to share insights about Ruby.
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In the past, I have given talks, including a tiny talk in 2008 and 2009.
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Additionally, I spoke about various topics including Ruby and code structure.
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About two years ago, I discussed local variables in particular.
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This year, I am excited to present my first talk on Ruby's local variables.
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I am nervous but ready to share my experiences.
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Currently, I work at a company in Creper, creating Ruby on Rails applications.
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I've been involved in developing educational services using Ruby.
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The product I work on is mainly utilized in Indonesia, the Philippines, and Mexico.
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In Japan, we refer to it as Study Support.
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We are also hiring, so if any of you know anyone, please send them my way.
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I live part-time in Vancouver and Tokyo.
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One favorite feature of Ruby is its dynamic nature.
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There are many ways to declare and utilize local variables.
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My talk will focus on different aspects of Ruby and local variables.
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One of the simple ways is to assign values directly to variables.
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For example, if we assign 1, 2, and 3 to X, it will be straightforward.
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So, if you type X, it will reference the assigned values.
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We can also use local variables as method parameters.
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When calling a method with parameters, those parameters become local variables.
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In Ruby, there are several special local variable declarations.
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One common feature is using eval; everybody knows eval, right?
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With eval, you can execute Ruby code dynamically.
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However, keep in mind that using eval could lead to context issues.
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If you don't properly declare variables before calling them, it can raise a NameError.
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Thus, wrapping lines of code using eval has its potential pitfalls.
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The Ruby binding method allows you to capture the local variable context.
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Once captured, you can manipulate the binding context effectively.
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This is handy, as it provides access to local variables.
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In summary, this demonstrates the flexibility and potential complexity of Ruby's local variables.
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I found that understanding these nuances helps in effective Ruby programming.
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The dynamic nature of Ruby and its handling of local variables is a powerful feature.
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I look forward to your questions and discussions about these concepts.
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Thank you for your attention!