38 lines
1.2 KiB
Plaintext
38 lines
1.2 KiB
Plaintext
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& Lesson 1: The World of the Turtle
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& Ludus is a Logo: it leads with turtle graphics
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& There are two panes on the right:
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& * the turtle
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& * the console
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& You saw the console in Lesson 0: Hello World!
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& `print!`ing things is very useful; remember you can do that.
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& Now, we're going to give the turtle some functions.
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forward! (100)
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& let's dissect that
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& forward! (100)
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& ^^^^^^^^ `forward!` is is the name of the function
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& ^^^^ `100` is how far the turtle should walk
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& (...) notice that we have to put 100 in parens
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& Uncomment the line below, and re-run the script:
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& right! (0.25)
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& right! (0.25)
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& ^^^^^^ `right!` is the name of this function
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& ^^^^ 0.25 is how far the turtle should turn
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& (....) notice again, we put the amount in parens
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& What is the unit of 0.25?
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& Try out some other turtle functions. Here are a few:
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& `left!`, `back!`, `penup!`, `pendown!`, `pencolor!`, `penwidth!`
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& `home!`
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& Note they all end with `!`. What happens if you forget the bang?
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& There are abbreviations: `fd!`, `rt!`, `lt!`, `bk!`, etc.
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& The turtle graphics functions (and abbreviations!) are listed at https://alea.ludus.dev/twc/ludus/src/branch/main/prelude.md#turtle-graphics
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