Mirrors/rust-cookbook
2
0
Fork 0
mirror of https://github.com/rust-lang-nursery/rust-cookbook synced 2024-11-25 13:00:21 +00:00
Code Issues Projects Releases Packages Wiki Activity

added verify email and extract login example

Browse source
This commit is contained in:
Ty Coghlan 2017-07-15 10:16:18 -04:00 committed by Michal Budzynski
parent 9e59de7bfa
commit f558c1fb76
2 changed files with 43 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

41
src/basics.md
View file

@ -12,6 +12,7 @@
| [Filter a log file by matching multiple regular expressions][ex-regex-filter-log] | [![regex-badge]][regex] | [![cat-text-processing-badge]][cat-text-processing]
| [Declare lazily evaluated constant][ex-lazy-constant] | [![lazy_static-badge]][lazy_static] | [![cat-caching-badge]][cat-caching] [![cat-rust-patterns-badge]][cat-rust-patterns] |
| [Maintain global mutable state][ex-global-mut-state] | [![lazy_static-badge]][lazy_static] | [![cat-rust-patterns-badge]][cat-rust-patterns] |
| [Verify and extract login from an email address][ex-verify-extract-email] | [![regex-badge]][regex] | [![cat-text-processing-badge]][cat-text-processing] |
| [Access a file randomly using a memory map][ex-random-file-access] | [![memmap-badge]][memmap] | [![cat-filesystem-badge]][cat-filesystem] |
| [Define and operate on a type represented as a bitfield][ex-bitflags] | [![bitflags-badge]][bitflags] | [![cat-no-std-badge]][cat-no-std] |
| [Extract a list of unique #Hashtags from a text][ex-extract-hashtags] | [![regex-badge]][regex] [![lazy_static-badge]][lazy_static] | [![cat-text-processing-badge]][cat-text-processing] |
@ -473,6 +474,46 @@ fn run() -> Result<()> {
# quick_main!(run);
```
[ex-verify-extract-email]: #ex-verify-extract-email
<a name="ex-verify-extract-email"></a>
## Verify and extract login from an email address
[![regex-badge]][regex] [![cat-text-processing-badge]][cat-text-processing]
Validates that an email address is formatted correctly, and extracts everything
before the @ symbol.
```rust
#[macro_use]
extern crate lazy_static;
extern crate regex;
use regex::Regex;
fn extract_login(input: &str) -> Option<&str> {
lazy_static! {
static ref RE: Regex = Regex::new(r"(?x)
^(?P<login>[^@\s]+)@
([[:word:]]+\.)*
[[:word:]]+$
").unwrap();
}
RE.captures(input).and_then(|cap| {
cap.name("login").map(|login| login.as_str())
})
}
fn main() {
assert_eq!(extract_login(r"I❤email@example.com"), Some(r"I❤email"));
assert_eq!(
extract_login(r"sdf+sdsfsd.as.sdsd@jhkk.d.rl"),
Some(r"sdf+sdsfsd.as.sdsd")
);
assert_eq!(extract_login(r"More@Than@One@at.com"), None);
assert_eq!(extract_login(r"Not an email@email"), None);
}
```
[ex-random-file-access]: #ex-random-file-access
<a name="ex-random-file-access"></a>
## Access a file randomly using a memory map

2
src/intro.md
View file

@ -30,6 +30,7 @@ community. It needs and welcomes help. For details see
| [Filter a log file by matching multiple regular expressions][ex-regex-filter-log] | [![regex-badge]][regex] | [![cat-text-processing-badge]][cat-text-processing]
| [Declare lazily evaluated constant][ex-lazy-constant] | [![lazy_static-badge]][lazy_static] | [![cat-caching-badge]][cat-caching] [![cat-rust-patterns-badge]][cat-rust-patterns] |
| [Maintain global mutable state][ex-global-mut-state] | [![lazy_static-badge]][lazy_static] | [![cat-rust-patterns-badge]][cat-rust-patterns] |
| [Verify and extract login from an email address][ex-verify-extract-email] | [![regex-badge]][regex] | [![cat-text-processing-badge]][cat-text-processing] |
| [Access a file randomly using a memory map][ex-random-file-access] | [![memmap-badge]][memmap] | [![cat-filesystem-badge]][cat-filesystem] |
| [Define and operate on a type represented as a bitfield][ex-bitflags] | [![bitflags-badge]][bitflags] | [![cat-no-std-badge]][cat-no-std] |
| [Extract a list of unique #Hashtags from a text][ex-extract-hashtags] | [![regex-badge]][regex] [![lazy_static-badge]][lazy_static] | [![cat-text-processing-badge]][cat-text-processing] |
@ -268,6 +269,7 @@ Keep lines sorted.
[ex-invalid-csv]: encoding.html#ex-invalid-csv
[ex-paginated-api]: net.html#ex-paginated-api
[ex-parse-subprocess-output]: basics.html#ex-parse-subprocess-output
[ex-verify-extract-email]: basics.html#ex-verify-extract-email
[ex-percent-encode]: encoding.html#ex-percent-encode
[ex-phone]: basics.html#ex-phone
[ex-rand-custom]: basics.html#ex-rand-custom