Sway Ref: Assertions assert_eq (FuelLabs#4688)

docs/reference/src/SUMMARY.md

@@ -85,6 +85,7 @@
   - [assert](./documentation/operations/assertions/assert.md)
   - [require](./documentation/operations/assertions/require.md)
   - [revert](./documentation/operations/assertions/revert.md)
+  - [assert_eq](./documentation/operations/assertions/assert-eq.md)
 - [Address Namespace](./documentation/operations/namespace/index.md)
   - [Address](./documentation/operations/namespace/address.md)
   - [ContractId](./documentation/operations/namespace/contract-id.md)

docs/reference/src/code/operations/assertions/src/lib.sw

@@ -2,14 +2,25 @@ library;
 
 mod req;
 
+#[allow(dead_code)]
 // ANCHOR: assert
 fn subtract(a: u64, b: u64) -> u64 {
     assert(b <= a);
     a - b
 }
 // ANCHOR_END: assert
+
+#[allow(dead_code)]
 fn reverts() {
     // ANCHOR: revert
     revert(42);
     // ANCHOR_END: revert
 }
+
+#[allow(dead_code)]
+// ANCHOR: assert_eq
+fn compare(a: u64, b: u64) {
+    assert_eq(a, b);
+    // code
+}
+// ANCHOR_END: assert_eq

docs/reference/src/documentation/operations/assertions/assert-eq.md

@@ -0,0 +1,11 @@
+# assert_eq
+
+The `assert_eq` function is automatically imported into every program from the [prelude](../../misc/prelude.md). It takes two expressions which are compared and the result is a [Boolean](../../language/built-ins/boolean.md). If the value is `false` then the virtual machine will revert.
+
+## Example
+
+Here is a function which asserts that `a` and `b` must be equal.
+
+```sway
+{{#include ../../../code/operations/assertions/src/lib.sw:assert_eq}}
+```

docs/reference/src/documentation/operations/assertions/index.md

@@ -12,3 +12,4 @@ Handling exceptions may be done through [if expressions](../../language/control-
 - [`assert`](assert.md): Checks if a `condition` is `true` otherwise reverts
 - [`require`](require.md): Checks if a `condition` is `true` otherwise logs a `value` and reverts
 - [`revert`](revert.md): Reverts the virtual machine with the provided exit code
+- [`assert_eq`](assert-eq.md): Checks if `a` and `b` are equal otherwise reverts