50 lines
1.6 KiB
Markdown
50 lines
1.6 KiB
Markdown
---
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title: Ruby Comments
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---
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<h1>Ruby Comments</h1>
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Comments are lines of annotation within code that are ignored at runtime (meaning they are visible within the source code but aren't printed out when you run the program).
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In Ruby, a single line comment starts with the `#` character and extends to the end of the line. The comment can be on its own line or following code.
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```Ruby
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puts "Learning to code is fun!"
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# I am a single line comment.
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puts "Ruby is a great language!" # Me too - I am a trailing comment.
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```
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When executed, the program above produces the following:
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```
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Learning to code is fun!
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Ruby is a great language!
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```
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You can do multiple line comments by putting the comments between `=begin` and `=end`. `=begin` and `=end` must start at the very beginning of the line and `=end` must be on a line of its own.
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```ruby
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=begin
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I am a multi-line comment
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and I can be as long as I please.
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See, still going!
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=end
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puts "Hello World!"
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=begin It's ok to start the comment on the same
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line as "=begin" (though it's more readable if
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you don't) but you can't put a space or any
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text before "=begin" or "=end" and you can't put
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anything on the same line after "=end".
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=end
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```
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When executed, the program above produces the following:
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```
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Hello World!
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```
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In general, it's best to use multi-line comments when explaining what your method does or for your program as a whole. Stick to single-line comments when clarifying a line or two of code, but when you find yourself expanding a file just to finish your single-line comment, consider using a multi-line comment instead.
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