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_archive/rhai_engine/rhaibook/engine/debugging/call-stack.md

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+Call Stack
+==========
+
+{{#include ../../links.md}}
+
+```admonish info.side.wide "Call stack frames"
+
+Each "frame" in the call stack corresponds to one layer of [function] call (script-defined
+or native Rust).
+
+A call stack frame has the type `debugger::CallStackFrame`.
+```
+
+The [debugger] keeps a _call stack_ of [function] calls with argument values.
+
+This call stack can be examined to determine the control flow at any particular point.
+
+The `Debugger::call_stack` method returns a slice of all call stack frames.
+
+```rust
+use rhai::debugger::*;
+
+let debugger = &mut context.global_runtime_state().debugger();
+
+// Get depth of the call stack.
+let depth = debugger.call_stack().len();
+
+// Display all function calls
+for frame in debugger.call_stack().iter() {
+    println!("{frame}");
+}
+```