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@@ -1,16 +1,63 @@
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---- exercises/106_files.zig 2024-05-05 00:48:25.808548611 +0200
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-+++ answers/106_files.zig 2024-05-05 01:00:40.742969819 +0200
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-@@ -35,7 +35,7 @@
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+--- exercises/106_files.zig 2024-06-17 10:11:53.651439869 +0200
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++++ answers/106_files.zig 2024-06-17 10:21:50.697337653 +0200
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+@@ -1,22 +1,22 @@
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+ //
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+ // Until now, we've only been printing our output in the console,
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+-// which is good enough for fighting aliens and hermit bookkeeping.
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++// which is good enough for fighting alien and hermit bookkeeping.
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+ //
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+-// However, many other tasks require some interaction with the file system,
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++// However, many other task require some interaction with the file system,
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+ // which is the underlying structure for organizing files on your computer.
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+ //
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+-// The file system provides a hierarchical structure for storing files
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+-// by organizing them into directories, which hold files and other directories,
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+-// thus creating a tree structure that can be navigated.
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++// The File System provide a hierarchical structure for storing files
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++// by organizing files into directories, which hold files and other directories,
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++// thus creating a tree structure for navigating.
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+ //
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+-// Fortunately, the Zig standard library provides a simple API for interacting
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+-// with the file system, see the detail documentation here:
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++// Fortunately, zig standard library provide a simple api for interacting
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++// with the file system, see the detail documentation here
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+ //
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+ // https://ziglang.org/documentation/master/std/#std.fs
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+ //
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+-// In this exercise, we'll try to:
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+-// - create a new directory,
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+-// - open a file in the directory,
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++// In this exercise, we'll try to
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++// - create a new directory
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++// - open a file in the directory
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+ // - write to the file.
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+ //
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+ // import std as always
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+@@ -27,42 +27,42 @@
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+ const cwd: std.fs.Dir = std.fs.cwd();
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+
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+ // then we'll try to make a new directory /output/
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+- // to store our output files.
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++ // to put our output files.
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+ cwd.makeDir("output") catch |e| switch (e) {
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+- // there is a chance you might want to run this
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++ // there are chance you might want to run this
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+ // program more than once and the path might already
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+- // have been created, so we'll have to handle this error
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++ // been created, so we'll have to handle this error
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// by doing nothing
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// by doing nothing
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//
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//
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// we want to catch error.PathAlreadyExists and do nothing
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// we want to catch error.PathAlreadyExists and do nothing
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- ??? => {},
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- ??? => {},
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+- // if there's any other unexpected error we just propagate it through
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+ error.PathAlreadyExists => {},
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+ error.PathAlreadyExists => {},
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- // if is any other unexpected error we just propagate it through
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++ // if is any other unexpected error we just propagate it through
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else => return e,
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else => return e,
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};
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};
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-@@ -44,7 +44,7 @@
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- // wait a minute
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+
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+ // then we'll try to open our freshly created directory
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+- // wait a minute...
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++ // wait a minute
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// opening a directory might fail!
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// opening a directory might fail!
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// what should we do here?
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// what should we do here?
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- var output_dir: std.fs.Dir = cwd.openDir("output", .{});
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- var output_dir: std.fs.Dir = cwd.openDir("output", .{});
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@@ -18,12 +65,36 @@
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defer output_dir.close();
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defer output_dir.close();
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// we try to open the file `zigling.txt`,
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// we try to open the file `zigling.txt`,
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-@@ -55,7 +55,7 @@
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+- // and propagate any error up
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++ // and propagate the error up if there are any errors
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+ const file: std.fs.File = try output_dir.createFile("zigling.txt", .{});
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+ // it is a good habit to close a file after you are done with it
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+ // so that other programs can read it and prevent data corruption
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// but here we are not yet done writing to the file
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// but here we are not yet done writing to the file
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- // if only there were a keyword in zig that
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- // allows you "defer" code execute to the end of scope...
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+- // if only there were a keyword in Zig that
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+- // allowed you to "defer" code execution to the end of the scope...
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- file.close();
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- file.close();
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++ // if only there were a keyword in zig that
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++ // allows you "defer" code execute to the end of scope...
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+ defer file.close();
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+ defer file.close();
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- // !you are not allowed to switch these two lines above the file closing line!
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+- // you are not allowed to move these two lines above the file closing line!
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++ // !you are not allowed to switch these two lines above the file closing line!
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const byte_written = try file.write("It's zigling time!");
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const byte_written = try file.write("It's zigling time!");
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+ std.debug.print("Successfully wrote {d} bytes.\n", .{byte_written});
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+ }
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+ // to check if you actually write to the file, you can either,
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+-// 1. open the file in your text editor, or
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++// 1. open the file on your text editor, or
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+ // 2. print the content of the file in the console with the following command
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+ // >> cat ./output/zigling.txt
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+ //
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+@@ -86,7 +86,7 @@
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+ //
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+ // Question:
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+ // - what should you do if you want to also read the file after opening it?
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+-// - go to the documentation of the struct `std.fs.Dir` here:
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++// - go to documentation of the struct `std.fs.Dir` here
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+ // https://ziglang.org/documentation/master/std/#std.fs.Dir
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+ // - can you find a function for opening a file? how about deleting a file?
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+ // - what kind of options can you use with those functions?
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