The class Post is a stream destination. Its main use is that it can sometimes make code more readable and execution slightly more efficient.
Post <<< a << " " <<< b << " " <<< c << " " <<< d << Char.nl;
vs
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(a.asCompileString + b.asCompileString + c.asCompileString + d.asCompileString).postln;
Post as string
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Post << "string";
Post as compile string
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Post <<< "string";
Prints a comma
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Post.comma;
Prints a space
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Post.space;
Prints a newline
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Post.nl;
Prints the char $\f
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Post.ff;
Prints a tab
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Post.tab;
a = "a string";
b = 'a symbol';
c = 4;
d = [1,2,3,4,a,b];
// post as string
Post << a << Char.nl;
// post as compile string
Post <<< a << Char.nl;
// post as string
Post << d << Char.nl;
// post as compile string
Post <<< d << Char.nl;
//This is the equivalent of :
d.postln;
//or
d.asCompileString.postln;