English fixes for 106_files.zig

This commit is contained in:
Andrew Dunbar 2024-06-12 17:52:33 +10:00
parent c9e5c7d561
commit 582a2558c7

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