# Calling Functions

## Call with Arguments

```cpp
int64_t args[] = { 10, 20 };
call(ctx, "add", args, 2);
int64_t result = return_value(ctx);  // 30
```

Arguments pass as `int64_t`. Floats must be bit-cast:

```cpp
double val = 3.14;
int64_t bits;
memcpy(&bits, &val, 8);

int64_t args[] = { bits };
call(ctx, "process_float", args, 1);

double result;
int64_t rbits = return_value(ctx);
memcpy(&result, &rbits, 8);
```

## Passing Strings

Allocate via Enma's heap:

```cpp
int64_t str = alloc_string(ctx, "hello world");
int64_t args[] = { str };
call(ctx, "process_text", args, 1);
```

Runtime manages the string's lifetime, don't free it manually.

## Reading String Returns

```cpp
execute(ctx, "get_name");
const char* name = return_string(ctx);
printf("name: %s\n", name);
```

The returned pointer is valid until the next call.

## Checking Function Existence

```cpp
if (has_function(mod, "on_tick")) {
    execute(ctx, "on_tick");
}
```

## Getting Parameter Count

```cpp
uint32_t params = function_param_count(mod, "add");  // 2
```


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