2018-01-04 00:15:04 +00:00
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# Function definitions
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2018-01-18 21:35:25 +00:00
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Syntax:
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`[<modifiers>] <return_type> <name> ( <params> ) [@ <address>] { <body> }`
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`asm <return_type> <name> ( <params> ) @ <address> extern`
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* `<modifiers>`: zero or more of the following:
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* `asm` – the function is written in assembly, not in Millfork (doesn't matter for `extern` functions),
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see [Using assembly within Millfork programs#Assembly functions](./assembly.md#assembly-functions)
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2018-02-01 21:39:38 +00:00
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* `macro` – the function is a macro,
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see [Macros_and inlining#Macros](../abi/inlining.md#macros)
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* `inline` and `noinline` – the function should preferably/should never be inlined
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see [Macros_and inlining#Inlining](../abi/inlining.md#automatic_inlining.md)
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2018-01-18 21:35:25 +00:00
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* `interrupt` – the function is a hardware interrupt handler
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* `<return_type>` is a valid return type, see [Types](./types.md)
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* `<params>` is a comma-separated list of parameters, in form `type name`. Allowed types are the same as for local variables.
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* `<address>` is a constant expression that defines where in the memory the function is or will be located.
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* `extern` is a keyword than marks functions that are not defined in the current program,
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but are likely to be available at certain address in memory.
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Such functions should be marked as written in assembly and should have their parameters passed through registers.
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* `<body>` is a newline-separated list of either Millfork or assembly statements
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