Fix E0387: Method Called on Trait Object Without Object Safety

Wed, 12 Aug 2026 12:44:04 +0800

1. Symptoms

When the Rust compiler encounters error E0387, you will see output similar to the following in your terminal:

error[E0387]: cannot call method `method_name` on a type `dyn TraitName`
  --> src/main.rs:12:5
   |
12 |     obj.method_name();
   |     ^^^^^^^^^^^^^^^^^ method `method_name` is not available on `dyn TraitName`
   |
   = note: method `method_name` has no `self` parameter
   = note: trait `TraitName` defines an item with this name, but this method cannot be dispatched to a trait object

Another variant of this error appears when you attempt to call a method that exists on the underlying type but is not part of the trait’s interface:

Fix E0689: method call has field expression before it

Tue, 04 Aug 2026 07:56:04 +0800

Fix E0689: method call has field expression before it

Rust’s compiler error E0689 indicates that the parser encountered a field expression followed by a method call in a way that doesn’t form valid syntax. This error typically emerges when developers confuse field access with method calls, attempt to call methods on temporary field values, or misplace parentheses and dots in chained expressions. Understanding the structure of Rust expressions and the distinction between fields and methods is essential for resolving this error.

Method-Call on ErrorVault — Developer Error Code Dictionary

Fix E0387: Method Called on Trait Object Without Object Safety

1. Symptoms

Fix E0689: method call has field expression before it

Fix E0689: method call has field expression before it