A better way...

module and_gate (out, in1, in2); input in1, in2; output out;

assign out = myfunction(in1, in2);

function myfunction;

input in1, in2;

begin

myfunction = in1 & in2;

end

endfunction

endmodule

Benefits:

Functions force a result

? Compiler will fail if function does not

generate a result

If you build a function wrong, the circuit

will not synthesize

? If you build an always block wrong,

you get a register

• Use functions for complex combinational logic

  • Functions can’t have state

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