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Runtime Management

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js_create

ant_t *js_create(void *buf, size_t len);
Creates a JavaScript runtime using a pre-allocated buffer. Parameters:
  • buf - Pre-allocated memory buffer
  • len - Size of the buffer in bytes
Returns: Pointer to the runtime, or NULL on failure

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js_create_dynamic

ant_t *js_create_dynamic();
Creates a JavaScript runtime with dynamic memory allocation (recommended). Returns: Pointer to the runtime, or NULL on failure

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js_destroy

void js_destroy(ant_t *js);
Destroys the runtime and frees all associated resources. Parameters:
  • js - Runtime instance

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js_setstackbase

void js_setstackbase(ant_t *js, void *base);
Sets the stack base pointer for stack overflow detection. Parameters:
  • js - Runtime instance
  • base - Pointer to stack base (typically a local variable address)

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js_setstacklimit

void js_setstacklimit(ant_t *js, size_t limit);
Sets the maximum stack size. Parameters:
  • js - Runtime instance
  • limit - Maximum stack size in bytes

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Evaluation Functions

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js_eval_bytecode

jsval_t js_eval_bytecode(ant_t *js, const char *code, size_t len);
Evaluates JavaScript bytecode. Parameters:
  • js - Runtime instance
  • code - JavaScript source code
  • len - Length of code string
Returns: Result value or error

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js_eval_bytecode_eval

jsval_t js_eval_bytecode_eval(ant_t *js, const char *code, size_t len);
Evaluates JavaScript code in eval mode (expression evaluation). Parameters:
  • js - Runtime instance
  • code - JavaScript source code
  • len - Length of code string
Returns: Result value or error

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js_eval_bytecode_module

jsval_t js_eval_bytecode_module(ant_t *js, const char *code, size_t len);
Evaluates JavaScript code as an ES module. Parameters:
  • js - Runtime instance
  • code - JavaScript source code
  • len - Length of code string
Returns: Result value or error

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js_eval_bytecode_repl

jsval_t js_eval_bytecode_repl(ant_t *js, const char *code, size_t len);
Evaluates JavaScript code in REPL mode. Parameters:
  • js - Runtime instance
  • code - JavaScript source code
  • len - Length of code string
Returns: Result value or error

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Value Creation

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js_mknum

jsval_t js_mknum(double value);
Creates a number value. Parameters:
  • value - Numeric value
Returns: JavaScript number value

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js_mkstr

jsval_t js_mkstr(ant_t *js, const void *data, size_t len);
Creates a string value. Parameters:
  • js - Runtime instance
  • data - String data
  • len - String length
Returns: JavaScript string value

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js_mkundef

jsval_t js_mkundef(void);
Creates an undefined value. Returns: JavaScript undefined value

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js_mknull

jsval_t js_mknull(void);
Creates a null value. Returns: JavaScript null value

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js_mkobj

jsval_t js_mkobj(ant_t *js);
Creates an empty object. Parameters:
  • js - Runtime instance
Returns: JavaScript object value

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js_mkarr

jsval_t js_mkarr(ant_t *js);
Creates an empty array. Parameters:
  • js - Runtime instance
Returns: JavaScript array value

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js_mkfun

jsval_t js_mkfun(jsval_t (*fn)(ant_t *, jsval_t *, int));
Creates a function from a C callback. Parameters:
  • fn - C function pointer with signature (ant_t *js, jsval_t *args, int nargs)
Returns: JavaScript function value Example: 
static jsval_t my_function(ant_t *js, jsval_t *args, int nargs) {
  // Function implementation
  return js_mknum(42);
}

jsval_t fn = js_mkfun(my_function);

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js_mkbigint

jsval_t js_mkbigint(ant_t *js, const char *digits, size_t len, bool negative);
Creates a BigInt value. Parameters:
  • js - Runtime instance
  • digits - String of decimal digits
  • len - Length of digits string
  • negative - Whether the value is negative
Returns: JavaScript BigInt value

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js_mksym

jsval_t js_mksym(ant_t *js, const char *desc);
Creates a Symbol value. Parameters:
  • js - Runtime instance
  • desc - Symbol description
Returns: JavaScript Symbol value

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Value Inspection

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vtype

uint8_t vtype(jsval_t val);
Gets the type of a JavaScript value. Parameters:
  • val - JavaScript value
Returns: Type constant (T_NUM, T_STR, T_BOOL, T_OBJ, T_ERR, T_UNDEF, T_NULL)

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js_getnum

double js_getnum(jsval_t val);
Extracts the numeric value from a number. Parameters:
  • val - JavaScript number value
Returns: Double-precision floating-point value

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js_getstr

char *js_getstr(ant_t *js, jsval_t val, size_t *len);
Extracts the string data from a string value. Parameters:
  • js - Runtime instance
  • val - JavaScript string value
  • len - Output parameter for string length
Returns: Pointer to string data

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js_str

const char *js_str(ant_t *js, jsval_t val);
Converts any value to a string representation. Parameters:
  • js - Runtime instance
  • val - JavaScript value
Returns: C string representation

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js_truthy

bool js_truthy(ant_t *js, jsval_t val);
Checks if a value is truthy. Parameters:
  • js - Runtime instance
  • val - JavaScript value
Returns: true if truthy, false otherwise

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Object Operations

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js_glob

jsval_t js_glob(ant_t *js);
Gets the global object. Parameters:
  • js - Runtime instance
Returns: Global object value

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js_set

void js_set(ant_t *js, jsval_t obj, const char *key, jsval_t val);
Sets a property on an object. Parameters:
  • js - Runtime instance
  • obj - Object value
  • key - Property name (C string)
  • val - Property value

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js_get

jsval_t js_get(ant_t *js, jsval_t obj, const char *key);
Gets a property from an object. Parameters:
  • js - Runtime instance
  • obj - Object value
  • key - Property name (C string)
Returns: Property value or undefined

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js_del

bool js_del(ant_t *js, jsval_t obj, const char *key);
Deletes a property from an object. Parameters:
  • js - Runtime instance
  • obj - Object value
  • key - Property name
Returns: true if deleted, false otherwise

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js_set_proto

void js_set_proto(ant_t *js, jsval_t obj, jsval_t proto);
Sets the prototype of an object. Parameters:
  • js - Runtime instance
  • obj - Object value
  • proto - Prototype object

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js_get_proto

jsval_t js_get_proto(ant_t *js, jsval_t obj);
Gets the prototype of an object. Parameters:
  • js - Runtime instance
  • obj - Object value
Returns: Prototype object

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Array Operations

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js_arr_len

jsoff_t js_arr_len(ant_t *js, jsval_t arr);
Gets the length of an array. Parameters:
  • js - Runtime instance
  • arr - Array value
Returns: Array length

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js_arr_get

jsval_t js_arr_get(ant_t *js, jsval_t arr, jsoff_t idx);
Gets an element from an array. Parameters:
  • js - Runtime instance
  • arr - Array value
  • idx - Array index
Returns: Element value

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js_arr_push

void js_arr_push(ant_t *js, jsval_t arr, jsval_t val);
Pushes a value to the end of an array. Parameters:
  • js - Runtime instance
  • arr - Array value
  • val - Value to push

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Property Iteration

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js_prop_iter_begin

ant_iter_t js_prop_iter_begin(ant_t *js, jsval_t obj);
Begins iterating over object properties. Parameters:
  • js - Runtime instance
  • obj - Object value
Returns: Iterator handle

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js_prop_iter_next

bool js_prop_iter_next(ant_iter_t *iter, const char **key, 
                       size_t *key_len, jsval_t *value);
Gets the next property in the iteration. Parameters:
  • iter - Iterator handle
  • key - Output parameter for property name
  • key_len - Output parameter for name length
  • value - Output parameter for property value
Returns: true if more properties exist, false when done

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js_prop_iter_end

void js_prop_iter_end(ant_iter_t *iter);
Ends property iteration and frees resources. Parameters:
  • iter - Iterator handle

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Context Functions

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js_getthis

jsval_t js_getthis(ant_t *js);
Gets the current this value. Parameters:
  • js - Runtime instance
Returns: Current this value

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js_setthis

void js_setthis(ant_t *js, jsval_t val);
Sets the current this value. Parameters:
  • js - Runtime instance
  • val - New this value

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js_getcurrentfunc

jsval_t js_getcurrentfunc(ant_t *js);
Gets the currently executing function. Parameters:
  • js - Runtime instance
Returns: Current function value

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Root Management

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js_root

jshdl_t js_root(ant_t *js, jsval_t val);
Roots a value to prevent garbage collection. Parameters:
  • js - Runtime instance
  • val - Value to root
Returns: Root handle

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js_unroot

void js_unroot(ant_t *js, jshdl_t handle);
Unroots a previously rooted value. Parameters:
  • js - Runtime instance
  • handle - Root handle

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js_deref

jsval_t js_deref(ant_t *js, jshdl_t handle);
Dereferences a root handle to get the value. Parameters:
  • js - Runtime instance
  • handle - Root handle
Returns: Rooted value

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Utility Functions

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js_chkargs

bool js_chkargs(jsval_t *args, int nargs, const char *types);
Checks if function arguments match expected types. Parameters:
  • args - Argument array
  • nargs - Number of arguments
  • types - Type specification string (e.g., “dd” for two numbers, “ds” for number and string)
Returns: true if arguments match, false otherwise Type codes:
  • d - Number
  • s - String
  • b - Boolean
  • o - Object
  • f - Function

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js_set_filename

void js_set_filename(ant_t *js, const char *filename);
Sets the current filename for error reporting. Parameters:
  • js - Runtime instance
  • filename - Filename string

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Constants

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Boolean Values

#define js_true   // JavaScript true
#define js_false  // JavaScript false
#define js_bool(x) // Converts C bool to JS boolean

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Special Numbers

#define JS_NAN      // Not a Number
#define JS_NEG_NAN  // Negative NaN
#define JS_INF      // Positive Infinity
#define JS_NEG_INF  // Negative Infinity

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Helper Macros

#define ANT_STRING(s)  // Creates string from C string literal
#define ANT_PTR(ptr)   // Converts pointer to number

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