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Undid changes involving misunderstanding of 0.3.x

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Didn't realise 0.3.0 referred to all 0.3.x versions! Fixed my mistakes. Should have just updated the Cargo.toml now.
This commit is contained in:
Ben Gesoff 2015-05-07 15:36:47 +01:00
parent 0bc6fe5ea0
commit 888086d959
1 changed files with 11 additions and 10 deletions
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21
src/doc/trpl/guessing-game.md
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@ -371,13 +371,15 @@ Now, without changing any of our code, let’s build our project:
```bash
$ cargo build
Updating registry `https://github.com/rust-lang/crates.io-index`
Downloading rand v0.3.0
Downloading rand v0.3.8
Downloading libc v0.1.6
Compiling libc v0.1.6
Compiling rand v0.3.0
Compiling rand v0.3.8
Compiling guessing_game v0.1.0 (file:///home/you/projects/guessing_game)
```
(You may see different versions, of course.)
Lots of new output! Now that we have an external dependency, Cargo fetches the
latest versions of everything from the registry, which is a copy of data from
[Crates.io][cratesio]. Crates.io is where people in the Rust ecosystem
@ -407,11 +409,11 @@ $ cargo build
Compiling guessing_game v0.1.0 (file:///home/you/projects/guessing_game)
```
Let's pretend that we told Cargo we wanted the latest version of `rand` (using `*`)
for a bit. It would have fetched `v0.3.8` (at the time this was written).
But what happens when next week, version `v0.3.9` comes out, with an important
bugfix? While getting bugfixes is important, what if `0.3.9` contains a regression
that breaks our code?
So, we told Cargo we wanted any `0.3.x` version of `rand`, and so it fetched the latest
version at the time this was written, `v0.3.8`. But what happens when next
week, version `v0.3.9` comes out, with an important bugfix? While getting
bugfixes is important, what if `0.3.9` contains a regression that breaks our
code?
The answer to this problem is the `Cargo.lock` file you’ll now find in your
project directory. When you build your project for the first time, Cargo
@ -419,7 +421,7 @@ figures out all of the versions that fit your criteria, and then writes them
to the `Cargo.lock` file. When you build your project in the future, Cargo
will see that the `Cargo.lock` file exists, and then use that specific version
rather than do all the work of figuring out versions again. This lets you
have a repeatable build automatically. In other words, we’ll stay at `0.3.0`
have a repeatable build automatically. In other words, we’ll stay at `0.3.8`
until we explicitly upgrade, and so will anyone who we share our code with,
thanks to the lock file.
@ -439,8 +441,7 @@ projects which are assembled out of a number of sub-packages.
[doccargo]: http://doc.crates.io
[doccratesio]: http://doc.crates.io/crates-io.html
Let’s get on to actually _using_ `rand`. Keep the version as `0.3.0` for this
project. Here’s our next step:
Let’s get on to actually _using_ `rand`. Here’s our next step:
```rust,ignore
extern crate rand;