Setup very first example with CI

.github/workflows/ci.yml

@@ -91,3 +91,22 @@ jobs:
         with:
           command: clippy
           args: -- -D warnings
+
+  examples:
+    name: Examples
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Install Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          components: clippy
+
+      - name: Run examples
+        run: |
+          for example in $(ls ./examples/); do
+            cargo run --bin $example
+          done

Cargo.toml

@@ -7,4 +7,5 @@ members = [
     "nutype_macros",
     "test_suite",
     "dummy",
+    "examples/*",
 ]

Justfile

@@ -1,4 +1,4 @@
-all: test-all clippy
+all: fmt test-all clippy examples
 
 test-all:
 	cargo test --features nutype_test
@@ -14,6 +14,9 @@ test:
 test-ui:
 	cargo test --features nutype_test,ui
 
+fmt:
+  cargo fmt
+
 watch:
 	cargo watch -x test
 
@@ -22,3 +25,6 @@ watch-dummy:
 
 clippy:
 	cargo clippy -- -D warnings
+
+examples:
+  for example in `ls examples`; do cargo run --bin $example; done

examples/float_sortable/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "float_sortable"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]
+nutype = { path = "../../nutype" }

examples/float_sortable/src/main.rs

@@ -0,0 +1,36 @@
+// This example shows how an f64 newtype can derive `Ord` and be sortable
+// if it defines `finite` validation.
+
+use nutype::nutype;
+
+#[nutype(derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord), validate(finite))]
+pub struct Width(f64);
+
+fn main() {
+    let raw_widths = vec![1.5, 1.4, 2.1, 1.8];
+
+    // NOTE: sorting raw_widths is not possible, because f64 does not implement Ord.
+    // raw_widths.sort();
+
+    // So instead we can wrap f64 into Width, which implements Ord.
+    // Ord is possible to safely derived, because there is `finite` validation in place,
+    // which excluded NaN values.
+    let mut widths: Vec<Width> = raw_widths
+        .into_iter()
+        .map(|w| Width::new(w).unwrap())
+        .collect();
+
+    // Now we can sort
+    widths.sort();
+
+    // Verify
+    assert_eq!(
+        widths,
+        vec![
+            Width::new(1.4).unwrap(),
+            Width::new(1.5).unwrap(),
+            Width::new(1.8).unwrap(),
+            Width::new(2.1).unwrap(),
+        ],
+    )
+}

examples/string_regex_email/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "string_regex_email"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+nutype = { path = "../../nutype", features = ["regex"] }
+regex = "1.10.2"
+lazy_static = "1.4.0"

examples/string_regex_email/src/main.rs

@@ -0,0 +1,42 @@
+use lazy_static::lazy_static;
+use nutype::nutype;
+use regex::Regex;
+
+lazy_static! {
+    // Note: this regex is very simplified.
+    // In reality you'd like to use a more sophisticated regex for email validation.
+    static ref EMAIL_REGEX: Regex = Regex::new("^\\w+@\\w+\\.\\w+$").unwrap();
+}
+
+// Note: technically the local part of email address is case-sensitive, but in practice all the
+// popular email services (e.g. gmail) make it case-insensitive, so applying `lowercase` is OK.
+#[nutype(
+    sanitize(trim, lowercase),
+    validate(
+        char_len_min = 5,
+        char_len_max = 20,
+        regex = EMAIL_REGEX,
+    ),
+    derive(Debug, PartialEq, AsRef),
+)]
+struct Email(String);
+
+fn main() {
+    // Too short
+    assert_eq!(Email::new("a@b"), Err(EmailError::CharLenMinViolated));
+
+    // Too long
+    assert_eq!(
+        Email::new("[email protected]"),
+        Err(EmailError::CharLenMaxViolated)
+    );
+
+    // Does not match the regex
+    assert_eq!(Email::new("foo@barcom"), Err(EmailError::RegexViolated));
+
+    // A valid email
+    let email: Email = Email::new("\t [email protected] \n").unwrap();
+
+    // The underlying string that represents the email address is sanitized
+    assert_eq!(email.as_ref(), "[email protected]");
+}

nutype_macros/src/any/gen/error.rs

@@ -35,6 +35,7 @@ fn gen_definition(error_type_name: &ErrorTypeName, validators: &[AnyValidator])
         .collect();
 
     quote! {
+        #[allow(clippy::enum_variant_names)]
         pub enum #error_type_name {
             #error_variants
         }

nutype_macros/src/float/gen/error.rs

@@ -55,6 +55,7 @@ fn gen_definition<T>(
         .collect();
 
     quote! {
+        #[allow(clippy::enum_variant_names)]
         pub enum #error_type_name {
             #error_variants
         }

nutype_macros/src/integer/gen/error.rs

@@ -51,6 +51,7 @@ fn gen_definition<T>(
         .collect();
 
     quote! {
+        #[allow(clippy::enum_variant_names)]
         pub enum #error_type_name {
             #error_variants
         }

nutype_macros/src/string/gen/error.rs

@@ -50,6 +50,7 @@ fn gen_definition(error_type_name: &ErrorTypeName, validators: &[StringValidator
         .collect();
 
     quote! {
+        #[allow(clippy::enum_variant_names)]
         pub enum #error_type_name {
             #error_variants
         }