rt-thread/components/external/espruino/src/jsparse.h

127 lines
5.2 KiB
C

/*
* This file is part of Espruino, a JavaScript interpreter for Microcontrollers
*
* Copyright (C) 2013 Gordon Williams <gw@pur3.co.uk>
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* ----------------------------------------------------------------------------
* Recursive descent parser for code execution
* ----------------------------------------------------------------------------
*/
#ifndef JSPARSE_H_
#define JSPARSE_H_
#include "jsvar.h"
#include "jslex.h"
typedef struct {
JsVar *root; ///< root of symbol table
} JsParse;
void jspInit(JsParse *parse);
void jspKill(JsParse *parse);
// jspSoft* - 'release' or 'claim' anything we are using, but ensure that it doesn't get freed
void jspSoftInit(JsParse *parse); ///< used when recovering from or saving to flash
void jspSoftKill(JsParse *parse); ///< used when recovering from or saving to flash
bool jspIsCreatedObject(JsParse *parse, JsVar *v); ///< Is v likely to have been created by this parser?
/** Returns true if the constructor function given is the same as that
* of the object with the given name. */
bool jspIsConstructor(JsVar *constructor, const char *constructorName);
/// Create a new built-in object that jswrapper can use to check for built-in functions
JsVar *jspNewBuiltin(const char *name);
/** Create a new object of the given instance and add it to root with name 'name'.
* If name!=0, added to root with name, and the name is returned
* If name==0, not added to root and Object itself returned */
JsVar *jspNewObject(JsParse *parse, const char *name, const char *instanceOf);
/// if interrupting execution, this is set
bool jspIsInterrupted();
/// if interrupting execution, this is set
void jspSetInterrupted(bool interrupt);
/// Has there been an error during parsing
bool jspHasError();
bool jspAddNativeFunction(JsParse *parse, const char *funcDesc, JsCallback callbackPtr);
JsVar *jspEvaluateVar(JsParse *parse, JsVar *str, JsVar *scope);
JsVar *jspEvaluate(JsParse *parse, const char *str);
bool jspExecuteFunction(JsParse *parse, JsVar *func, JsVar *parent, int argCount, JsVar **argPtr);
/// Evaluate a JavaScript module and return its exports
JsVar *jspEvaluateModule(JsParse *parse, JsVar *moduleContents);
/** When parsing, this enum defines whether
we are executing or not */
typedef enum {
EXEC_NO = 0,
EXEC_YES = 1,
EXEC_BREAK = 2,
EXEC_CONTINUE = 4,
EXEC_INTERRUPTED = 8, // true if execution has been interrupted
EXEC_ERROR = 16,
EXEC_ERROR_LINE_REPORTED = 32, // if an error has been reported, set this so we don't do it too much
EXEC_FOR_INIT = 64, // when in for initialiser parsing - hack to avoid getting confused about multiple use for IN
EXEC_IN_LOOP = 128, // when in a loop, set this - we can then block break/continue outside it
EXEC_IN_SWITCH = 256, // when in a switch, set this - we can then block break outside it/loops
EXEC_RUN_MASK = EXEC_YES|EXEC_BREAK|EXEC_CONTINUE|EXEC_INTERRUPTED,
EXEC_ERROR_MASK = EXEC_INTERRUPTED|EXEC_ERROR,
EXEC_SAVE_RESTORE_MASK = EXEC_YES|EXEC_IN_LOOP|EXEC_IN_SWITCH, // the things JSP_SAVE/RESTORE_EXECUTE should keep track of
} JsExecFlags;
/** This structure is used when parsing the JavaScript. It contains
* everything that should be needed. */
typedef struct {
JsParse *parse;
JsLex *lex;
// TODO: could store scopes as JsVar array for speed
JsVarRef scopes[JSPARSE_MAX_SCOPES];
int scopeCount;
/// Value of 'this' reserved word
JsVar *thisVar;
JsExecFlags execute;
} JsExecInfo;
/// flags for jspParseFunction
typedef enum {
JSP_NOSKIP_A = 1,
JSP_NOSKIP_B = 2,
JSP_NOSKIP_C = 4,
JSP_NOSKIP_D = 8,
JSP_NOSKIP_E = 16,
JSP_NOSKIP_F = 32,
JSP_NOSKIP_G = 64,
JSP_NOSKIP_H = 128,
} JspSkipFlags;
/// parse function with max 4 arguments (can set arg to 0 to avoid parse). Usually first arg will be 0, but if we DON'T want to skip names on an arg stuff, we can say
bool jspParseFunction(JspSkipFlags skipName, JsVar **a, JsVar **b, JsVar **c, JsVar **d);
/// parse function with max 8 arguments (can set arg to 0 to avoid parse). Usually first arg will be 0, but if we DON'T want to skip names on an arg stuff, we can say
bool jspParseFunction8(JspSkipFlags skipName, JsVar **a, JsVar **b, JsVar **c, JsVar **d, JsVar **e, JsVar **f, JsVar **g, JsVar **h);
bool jspParseVariableName(); ///< parse single variable name
bool jspParseEmptyFunction(); ///< parse function with no arguments
JsVar *jspParseSingleFunction(); ///< parse function with a single argument, return its value (no names!)
JsVar *jspParseFunctionAsArray(); ///< parse a function with any number of argument, and return an array of de-named aruments
/** Handle a function call (assumes we've parsed the function name and we're
* on the start bracket). 'thisArg' is the value of the 'this' variable when the
* function is executed (it's usually the parent object)
*
* If !isParsing and arg0!=0, argument 0 is set to what is supplied (same with arg1)
*
* functionName is used only for error reporting - and can be 0
*/
JsVar *jspeFunctionCall(JsVar *function, JsVar *functionName, JsVar *thisArg, bool isParsing, int argCount, JsVar **argPtr);
#endif /* JSPARSE_H_ */