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Update function definition description

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David Schmenk 2016-01-13 12:05:35 -08:00
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README.md
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@ -288,7 +288,7 @@ byte[64] txtfile = "UNTITLED"
#### Function Definitions
Functions are defined after all constants, variables and data. Function definitions can be `export`ed for inclusion in other modules and can be forward declared with a `predef` type in the constant and variable declarations. Functions can take parameters, passed on the evaluation stack, then copied to the local frame for easy access They can have their own variable declarations, however, unlike the global declarations, no data can be predeclared - only storage space. There is also a limit of 254 bytes of local storage. Each parameter takes two bytes of local storage, plus two bytes for the previous frame pointer. If a function has no parameters or local variables, no local frame will be created, improving performance. A function can specify a value to return. If no return value is specified, a default of 0 will be returned.
Functions are defined after all constants, variables and data. Function definitions can be `export`ed for inclusion in other modules and can be forward declared with a `predef` type in the constant and variable declarations. Functions can take parameters, passed on the evaluation stack, then copied to the local frame for easy access. They can have their own variable declarations, however, unlike the global declarations, no data can be predeclared - only storage space. A local frame is built for every function invokation and there is also a limit of 254 bytes of local storage. Each parameter takes two bytes of local storage, plus two bytes for the previous frame pointer. If a function has no parameters or local variables, no local frame will be created, improving performance. Functions always return a value; a function can specify a value to return or, if no return value is specified, a default of 0 will be returned.
Note: there is no mechanism to ensure caller and callee agree on the number of parameters. Historically, programmers have used Hungarian Notation (http://en.wikipedia.org/wiki/Hungarian_notation) to embed the parameter number and type in the function name itself. This is a notational aid; the compiler enforces nothing.