mirror of
https://github.com/ratfactor/ziglings
synced 2024-05-05 01:56:03 +02:00
42 lines
1.2 KiB
Zig
42 lines
1.2 KiB
Zig
//
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// Now let's use pointers to do something we haven't been
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// able to do before: pass a value by reference to a function.
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//
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// Why would we wish to pass a pointer to an integer variable
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// rather than the integer value itself? Because then we are
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// allowed to *change* the value of the variable!
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//
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// +-----------------------------------------------+
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// | Pass by reference when you want to change the |
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// | pointed-to value. Otherwise, pass the value. |
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// +-----------------------------------------------+
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//
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const std = @import("std");
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pub fn main() void {
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var num: u8 = 1;
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var more_nums = [_]u8{ 1, 1, 1, 1 };
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// Let's pass the num reference to our function and print it:
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makeFive(&num);
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std.debug.print("num: {}, ", .{num});
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// Now something interesting. Let's pass a reference to a
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// specific array value:
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makeFive(&more_nums[2]);
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// And print the array:
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std.debug.print("more_nums: ", .{});
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for (more_nums) |n| {
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std.debug.print("{} ", .{n});
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}
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std.debug.print("\n", .{});
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}
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// This function should take a reference to a u8 value and set it
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// to 5.
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fn makeFive(x: *u8) void {
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??? = 5; // fix me!
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}
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