I am new to Rust but when I run the chapter 2-complex example codes, then there is an error like below.

error[E0658]: use of unstable library feature 'dec2flt': internal routines only exposed for testing
 --> src/main.rs:1:5
  |
1 | use core::num::dec2flt::number;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^

Rust & Cargo version

• 1.62.0

The issue can be seen here:

Multiple patterns overlap on their endpoints here:

code for needle-in-haystack is missing. I wanted to double check here as the octal 0o204; doesnt match anything and prints nothing to the console.

Hi

I think in line 73 the x_min parameter that is passed to the calculate_mandelbrot function should be a negative value.
For the positive 2 that's used in the book I don't get any results in the console, just spaces.

I'm not really sure how to fix it, but it won't compile. Listing 1.2 on page 9.

I tried updating rust, etc but nothing changed

Obviously I'm at the start of the book so can't offer much help, but if I figure out the solution I'll leave a reply here.

Working with actionkv2 a bit and it looks like the "delete" keyword is broken for the disk version.

.\akv_disk.exe test_disk insert MN StPaul

.\akv_disk.exe test_disk insert PA Harrisburgh

.\akv_disk.exe test_disk get MN
OUTPUT: [83, 116, 80, 97, 117, 108]

.\akv_disk.exe test_disk delete MN

.\akv_disk.exe test_disk get MN
OUTPUT: [83, 116, 80, 97, 117, 108]

I think it's just adding the store_on_disk after updating the in memory kv. I made the change locally and it seems to be working.

"delete" => {
a.delete(key).unwrap();
store_index_on_disk(&mut a, INDEX_KEY);
}

I wasn't able to run the basic starting example. The shown configuration and tools are both incomplete and not updated. When trying to build using bootimage, the command is now different (cargo bootimage) and in particular there was an error about not being able to find the crate core.

It's thus incomplete because cargo-xbuild is installed but not actually used. Fortunately, I knew there was another tutorial on writing a kernel with Rust where I found the updated information: https://os.phil-opp.com/minimal-rust-kernel/

Basically, with Rust nightly 2020–07–15, we can now just simply write this in .cargo/config.toml:

[unstable]
build-std = ["core", "compiler_builtins", "alloc"]

Also this is much better because I was also able, with the latest version which fixed a bug with the nightly toolchain, to continue using rust-analyzer in vscode. OTOH, you are left with no intellisense with cargo-xbuild.

I hope this info will be helpful for someone, you can see the source code of the chapter with updated configuration at https://github.com/jiayihu/lab/tree/master/rust/fledge-os

The text reads:
Listing 2.2 prints a + b = 30 to the console

However, the code says: println!("( a + b ) + ( c + d ) = {}", e);

So it should say:
Listing 2.2 prints ( a + b ) + ( c + d ) = 90 to the console

The source code of this example uses [email protected] to send HTTP requests, perhaps this is for the reason that the newer version of reqwest switches to async mode on the top of tokio.
If you wanna use the newer version of reqwest and still send sync requests, use the code snippet below:

// main.rs
use std::error::Error;

use reqwest;

fn main() -> Result<(), Box<dyn Error>> { 
    let url = "http://www.rustinaction.com/";
    let mut response = reqwest::blocking::get(url)?; // use reqwest::blocking::get() to send sync request 

    let content = response.text()?;
    print!("{}", content);

    Ok(())
}

// Cargo.toml
...
[dependencies]
reqwest = { version="0.11.8", features = ["blocking"] } // ! enable the blocking feature

BTW, here is the link to reqwest::blocking.
:)

in ch2-mandelbrot, line 58 misses the = for the inclusive range:

11..30 => '*',

should be

11..=30 => '*',

Seems this was overseen in commit 509fe8c

I realized that you don't accept PRs so I thought opening this issue is a better way.

Chapter 5.5.5 CPU 4: Adding the rest briefly talks about a cpu4.
However, the code for cpu4 is missing.

With a few extra opcodes, it’s possible to implement multiplication and many more functions within your
inchoate CPU. Check the source code that comes along with the book (specifically the directory ch5/ch5-cpu4) for a mostly-complete fuller implementation of the CHIP-8 specification.

In https://github.com/rust-in-action/code/blob/1st-edition/ch9/ch9-clock3/src/main.rs#L40-L50:

impl NTPResult {
  fn offset(&self) -> i64 {
    let delta = self.delay();
    delta.abs() / 2
  }

  fn delay(&self) -> i64 {
    let duration = (self.t4 - self.t1) - (self.t3 - self.t2);
    duration.num_milliseconds()
  }
}

The definition of offset is incorrect (source on Wikipedia). Offset can be positive or negative, whereas delay is always positive. You can see that the equations above always return positive values.

Offset should let delta = (self.t2 - self.t1) - (self.t3 - self.t4);. Currently, it rearranges to let delta = (self.t2 - self.t1) - (self.t4 - self.t3);, i.e. the last two terms are swapped.

(I see there was an attempt to correct in #51, but as the OP later noted, the PR did not fix the issue.)

The code seems to use pre rust-2018 conventions. For example in the first chapter the code:

extern crate serde_derive;   // <3>
...
#[derive(Serialize)] // <6> Automatically generate a string representation of this struct (which will be used as JSON)
struct Timestamp { // <7> Syntax to create a custom type 

Can be re-written as

use serde::Serialize;
...
#[derive(Serialize)] // <6> Automatically generate a string representation of this struct (which will be used as JSON)
struct Timestamp { // <7> Syntax to create a custom type 

Hi, thanks for the book and the much helping source code.
I think I found a problem here:

Both this code and the book wording threw me off balance enough to check the wikipedia article, as your code doesn't have any difference between delta and theta, except for the 2 factor. their fixed definitions makes much more sense.

#[allow(arithmetic_overflow)]    <1>

fn main() {
  let (a, b) = (200, 200);
  let c: u8 = a + b;             <2>
  println!("200 + 200 = {}", c);
}

In this source code, there are two marks <1>/<2> the author might forget to comment, making the rustc reject to compile it

Take chapter5 I'm reading as example. (MEAP v15)

TBH, in Listing 5.14, I don't know why this is the way to converto from f64 to q7:

impl From<f64> for Q7 {
    fn from (n: f64) -> Self {
        if n >= 1.0 {
            Q7(127)
        } else if n <= -1.0 {
            Q7(-128)
        } else {
            Q7((n * 128.0) as i8)   // especially here, which confused me, why can't we just use first 7bits in mantissa part of that *f64* number.
        }
    }
}

Until I'm reading this(full definition): https://en.wikipedia.org/wiki/Q_(number_format)
And I finally understand your code. So in this context, if there are some external reference for q7 definition, it can help me to better understand your code. And make user understand more if he/she interests on this.

The source code for listing 7.14 seems to be missing from the 1st-edition branch

I'm unable to set the time of the OS in Ubuntu 18.04. I run the following command (at the time of writing the time is 13:28):

sudo ./target/debug/clock set -s rfc3339 2020-08-13T17:14:26.604583031+02:00

I don't get any error in std error, os_error_code is Some(0). If I remove the sudo I can see the permission error as expected:

Unable to set the time: Os { code: 1, kind: PermissionDenied, message: "Operation not permitted" }

What command should I use to set time OS time?

In listing 2.12 Rendering the Mandlebrot set,

hint number (6) says create rows with_capacity(width). Shouldn't that be ideally with_capacity(height) since we want to create height number of rows and passing height is much better?

Also few line below:

After upgrading to smoltcp 0.6.0 and fixing the MAC unicast bit (#7), the mget example seems to hang in the Request state waiting for .may_send() to return true.

I was able to fix this by adjusting the default gateway IP. From the referenced HTTP client example in the smoltcp docs (thanks for linking to that!) it looks like the default gateway IP should match the IP assigned to the TAP device with ip addr add.

In the book, the TAP device is given IP 192.168.42.100 (via sudo ip addr add 192.168.42.100/24 dev tap-rust), but the default gateway IP used in the code is 192.168.20.1 (http.rs, let default_gateway = Ipv4Address::new(192, 168, 20, 1);).

I changed that line to let default_gateway = Ipv4Address::new(192, 168, 42, 100);, and the example then ran correctly and I got a response from the server.

Hi Tim!

Rust in Action recently went from MEAP to final release, but I've noticed that this repository doesn't always match the code examples mentioned in the book.

E.g., in §2.1.1 Compiling single files with rustc it says:

You’ll find the source code for listing 2.1 in the file ch2/ok.rs

But the file ch2/ok.rs is only found in the code downloaded from Manning, not in this repo (see PR #34).

The Zip code from Manning is from MEAP 12 of the book. So I was wondering:

• Which should be the best code reference for the book, the Zip from Manning or this repository?
• Will the repository be updated to mirror the final book? or is the code of the repository being developed independently?

Hi Tim,

in code/ch7/ch7-actionkv1/src/lib.rs line 196..=198:
let next_byte = SeekFrom::End(0);
let current_position = f.seek(SeekFrom::Current(0))?;
f.seek(next_byte)?;

current_position does not necessarily reflects the end of the file, but a new record should always go to the end.

so, shouldn't it be just simple a one line:
let current_position = f.seek(SeekFrom::End(0))?;

Thanks for clarification
Jens

The ch12/noop from section 12.7 doesn't exists

This should be calculate_mandelbrot(1000, -2.0, 1.0, -1.0, 1.0, 80, 24) as mentioned in https://www.reddit.com/r/rust/comments/o980ip/rust_in_action_is_released/h3aktuf

for region in regions.iter() {               // <5>
      println!("{}", &region);             // <6>
}

In this code, region is a &&str, so why is another & used before region?

The book has been released! I need to update the code to match.

• Title of Listing 5.3:

Listing 5.3. Inspecting a float’s bit string by interpreting its bits as an integer (ch1-f32-as-u32.rs)**

Is it should be: Listing 5.3. Inspecting a float’s bit string by interpreting its bits as an integer (ch5-f32-as-u32.rs) ?

• the bottom of P133:

To print a value a individual bits, the type of that value must implement fmt::Display. f32 doesn’t implement fmt::Binary

Is it should be: To print a value a individual bits, the type of that value must implement fmt::Binary. f32 doesn’t implement fmt::Binary?

• Title of Listing 5.6:

Listing 5.6. Impossible Addition (ch1/ch1-impossible-addition.rs)

Is it should be: Listing 5.6. Impossible Addition (ch5/ch5-impossible-addition.rs)

Addition to listing 5.6, rustc can caught such error.(I'm running rustc 1.49.0). It tells me such error message:

error: this arithmetic operation will overflow
 --> src\bin\ch5-to-oblivion.rs:3:17
  |
3 |     let c: u8 = a + b;
  |                 ^^^^^ attempt to compute `200_u8 + 200_u8`, which would overflow
  |
  = note: `#[deny(arithmetic_overflow)]` on by default

rustc is more powerful now :-)

• Listing 5.7. Inspecting Endianness (ch1-endianness.rs)

Is it should be: Listing 5.7. Inspecting Endianness (ch5-endianness.rs)

Hope it can help... Maybe I can find something more, and I will update here :-)

As a MacOS user, it would be nice to have the alternative version of the same code to inspect the virtual memory in Linux. Having a Linux example based on POSIX seems reasonable.

Personally, showing a Windows-only example felt also a bit out of context to me. Right some lines before, the book was showing a very cool picture of ELF (which AFAIK is Linux-only) and I was intrigued to learn more, then it jumps to Windows code.

The code @ Animals specialization is not compiling
or is it a codeexample the shows what does not work
Sorry newb here, google brought me here when i was searching for specialization/generics.

Regards Remco

Was randomly skimming on manning and I'm encountering a lot of garbage text. I'm not sure if its specific to this book or a general issue with manning. However, I randomly tried book Full Stack Python and that renders without issue.

All chapters seem to be affected. At least, Chapters 4.1, 5, 6, 7.4.1 I've directly looked at.

AFAICT:

1. Intro paragraph per chapter seems to consistently render correctly.
2. First paragraph of first section per chapter sometimes renders correctly, sometimes doesn't.
3. Code blocks render correctly. The line preceding a codeblock renders incorrectly, sometimes
4. Paragraphs otherwise render as garbage
5. Links, Headers & Inline Code always render correctly

Windows 10
Chrome Version 91.0.4472.124 (Official Build) (64-bit)

No extensions, ad blockers, etc.
Tried refreshing, killing cookies, browser, etc.

There are a couple JS errors occurring, but since they exist for both books, I don't think that's the issue.

Rust In Action - garbage text

Full Stack Python - renders correctly

I've seen a couple other issues for this section in particular, but I tried compiling the code from the repo as is and I got the following error:

➜  ch2-mandelbrot git:(1st-edition) ✗ cargo run                   
   Compiling autocfg v1.0.0
   Compiling num-traits v0.2.12
   Compiling num-integer v0.1.43
   Compiling num-bigint v0.3.0
   Compiling num-rational v0.3.0
   Compiling num-iter v0.1.41
   Compiling num-complex v0.3.0
   Compiling num v0.3.0
   Compiling ch2-mandelbrot v0.1.0 (/Users/ethanarrowood/Documents/Programming/rust/rust-in-action/code/ch2/ch2-mandelbrot)
error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:55:9
   |
55 |         0..2 => ' ',
   |         ^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:56:9
   |
56 |         2..5 => '.',
   |         ^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:57:9
   |
57 |         5..10 => '•',
   |         ^^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:58:9
   |
58 |         11..30 => '*',
   |         ^^^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:59:9
   |
59 |         30..100 => '+',
   |         ^^^^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:60:9
   |
60 |         100..200 => 'x',
   |         ^^^^^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

error[E0658]: exclusive range pattern syntax is experimental
  --> src/main.rs:61:9
   |
61 |         200..400 => '$',
   |         ^^^^^^^^
   |
   = note: see issue #37854 <https://github.com/rust-lang/rust/issues/37854> for more information

warning: unnecessary parentheses around assigned value
  --> src/main.rs:20:23
   |
20 |       let x_percent = (img_x as f64 / width as f64);
   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
   |
   = note: `#[warn(unused_parens)]` on by default

warning: unnecessary parentheses around assigned value
  --> src/main.rs:21:23
   |
21 |       let y_percent = (img_y as f64 / height as f64);
   |                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses

error: aborting due to 7 previous errors; 2 warnings emitted

For more information about this error, try `rustc --explain E0658`.
error: could not compile `ch2-mandelbrot`

To learn more, run the command again with --verbose.

I also ran rustup update stable earlier; do I need to be on a different rust version to run this one? From the referenced github issue it states I should add #![feature(exclusive_range_pattern)] to the top of the file and install the nightly build of rust to run it.

Hello buddy!

Great book! Found a trivial discrepancy in Listing 2.21

The result in the LiveBook is shown as:

[1, 2, 3]: 1 + 10 = 11 2 + 10 = 12 3 + 10 = 13 (Σ[1, 2, 3] = 6)
[1, 2, 3]: 1 + 10 = 11 2 + 10 = 12 3 + 10 = 13 (Σ[1, 2, 3] = 6)
[0, 0, 0]: 0 + 10 = 10 0 + 10 = 10 0 + 10 = 10 (Σ[0, 0, 0] = 0)
[0, 0, 0]: 0 + 10 = 10 0 + 10 = 10 0 + 10 = 10 (Σ[0, 0, 0] = 0)

The sum bit has the sum symbol Σ but the code doesn't have it.

The code as is is missing the Σ symbol:

fn main() {
  let one             = [1, 2, 3];
  let two: [u8; 3]    = [1, 2, 3];
  let blank1          = [0; 3];
  let blank2: [u8; 3] = [0; 3];
 
  let arrays = [one, two, blank1, blank2];
 
  for a in &arrays {
    print!("{:?}: ", a);
    for n in a.iter() {
      print!("\t{} + 10 = {}", n, n+10);
    }
 
    let mut sum = 0;
    for i in 0..a.len() {
      sum += a[i];
    }
    println!("\t({:?} = {})", a, sum);
  }
}

Line 19 should be:

      print!("\tΣ{} + 10 = {}", n, n+10);

As can be seen here, the extra closing brace prevents compilation.

Removing the brace solves the issue.

all_rows doesn't exist in this scope:

In Listing 3.15,

   fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
     match *self {
         FileState::Open => write!(f, "OPEN"),      // <4>
         FileState::Closed => write!(f, "CLOSED"),  // <4>
     }

In fact, a & is not necessary, and using match self directly would be more easily understood.

At the beginning of the section 8.4 (TCP), we can see some code listings from ch8/ch8-stdlib but i can't find the code into this repository.

Section 7.7.11 points out a problem of actionkv v1 is that it has long start up time and describes a way to shorten it by storing the index itself on the database. But actionkv v2 still reads all of the database file and rebuilds the index. Thus the problem of actionkv v1 is not resolved. Considring the discussion of this section, I think it should be resolved.

Livebook has a reference The code for this listing is in ch2/ch2-needle-in-haystack.rs., which isn't included in the source code

I try to build mget on rust v1.60 on mac and the build fails because of:

➜  ch8-mget git:(1st-edition) ✗ cargo build
   Compiling mget v0.1.0 (/Users/adria/Programming/rust-in-action/ch8/ch8-mget)
error[E0432]: unresolved import `smoltcp::phy::TapInterface`
 --> src/main.rs:2:5
  |
2 | use smoltcp::phy::TapInterface;
  |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ no `TapInterface` in `phy`

error[E0432]: unresolved import `smoltcp::phy::TapInterface`
 --> src/http.rs:7:38
  |
7 | use smoltcp::phy::{wait as phy_wait, TapInterface};
  |                                      ^^^^^^^^^^^^ no `TapInterface` in `phy` 

I also had to modify Cargo.toml because curly bracket content cannot be separated over several lines.

In my IDE, I can however see that TapInterface exists.
Any idea?

I noticed that the stack overflow check is out by one as it's comparing to len() with > rather than >=. I've created a PR to illustrate the issue, although as I added to tests to show it so it's probably not suitable for that chapter of the book.

Spotted in MEAP v16.

Thanks for writing a great book :)

Hi Tim,

It seems like there are two problems with the ch8-mget example, first the default version of smoltcp 0.5 no longer compiles, I updated to 0.6 and that worked. The second is the example seems to have issues with ethernet not being unicast

❯ cargo run http://www.rustinaction.com/ tap-rust -s 8.8.8.8
warning: unused manifest key: profile.release.codegen_units
warning: trait objects without an explicit `dyn` are deprecated
  --> src/dns.rs:40:101
   |
40 | pub fn resolve(dns_server_address: &str, domain_name: &str) -> Result<Option<std::net::IpAddr>, Box<Error>> {
   |
                            ^^^^^ help: use `dyn`: `dyn Error`
   |
   = note: `#[warn(bare_trait_objects)]` on by default

    Finished dev [unoptimized + debuginfo] target(s) in 0.07s
     Running `/home/user/build-artifacts/debug/mget 'http://www.rustinaction.com/' tap-rust -s 8.8.8.8`
thread 'main' panicked at 'Ethernet address f7-f0-a7-28-e7-57 is not unicast', /home/user/.cargo/registry/src/github.com-1ecc6299db9ec823/smoltcp-0.6.0/src/iface/ethernet.rs:705:13

At line 46 of Listing 2.22,

for &(i, ref line) in local_ctx.iter()

I think introducing ref here would pose a burden for understanding. A better and simpler way:

for (i, line) in local_ctx.iter()

Both ways are to borrow, not move.

MEMORY_BASIC_INFORMATION is imported on this line as MEMINFO, but this line still uses the original import name.

Updating line 22 to MEMINFO fixes the issue.

This section discusses storing the index in with the data to avoid having to rebuild it on load, though it seems looking at the code the entire index is still built on every load. So it would provide no benefit I believe. (though is an interesting description of in-lining the index in with the data)

running cargo +nightly run on ch11/ch11-fledge-os-0 returns the following:

error[E0557]: feature has been removed
 --> /home/username/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/x86_64-0.13.5/src/lib.rs:5:43
  |
5 | #![cfg_attr(feature = "const_fn", feature(const_fn))] // Needed for generic access to associated consts
  |                                           ^^^^^^^^ feature has been removed
  |
  = note: split into finer-grained feature gates

For more information about this error, try `rustc --explain E0557`.

no issues opened for this in https://github.com/rust-osdev/x86_64, related rust-lang/rust#84510

any help appriciated!

Note that the snippet for ch5/ch5-visualizing-f32.rs is missing the mantissa variable. This can be easily fixed by adding this before the for loop in decode. He does mention this in the book but the listing seems to be missing it.

let mut mantissa: f32 = 1.0;