zig/lib/std / io/seekable_stream.zig 

const std = @import("../std.zig");

SeekableStream()

 
pub fn SeekableStream(
    comptime Context: type,
    comptime SeekErrorType: type,
    comptime GetSeekPosErrorType: type,
    comptime seekToFn: fn (context: Context, pos: u64) SeekErrorType!void,
    comptime seekByFn: fn (context: Context, pos: i64) SeekErrorType!void,
    comptime getPosFn: fn (context: Context) GetSeekPosErrorType!u64,
    comptime getEndPosFn: fn (context: Context) GetSeekPosErrorType!u64,
) type {
    return struct {
        context: Context,

        const Self = @This();
        pub const SeekError = SeekErrorType;
        pub const GetSeekPosError = GetSeekPosErrorType;

seekTo()

 
        pub fn seekTo(self: Self, pos: u64) SeekError!void {
            return seekToFn(self.context, pos);
        }

seekBy()

 
        pub fn seekBy(self: Self, amt: i64) SeekError!void {
            return seekByFn(self.context, amt);
        }

getEndPos()

 
        pub fn getEndPos(self: Self) GetSeekPosError!u64 {
            return getEndPosFn(self.context);
        }

getPos()

 
        pub fn getPos(self: Self) GetSeekPosError!u64 {
            return getPosFn(self.context);
        }
    };
}