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fish-shell/src/tinyexpr.h

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Replace muparser with tinyexpr
2018-02-11 02:46:34 +08:00
/*
* TINYEXPR - Tiny recursive descent parser and evaluation engine in C
*
* Copyright (c) 2015, 2016 Lewis Van Winkle
*
* http://CodePlea.com
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgement in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
[tinyexpr] Port to C++ This removes the need to run c-compilation on one file, and allows us to in future c++-ify this a bit. There's a lot of bit-fiddling here that is quite unnecessary, better error-handling would be nice... So far this removes a few more unused things (because I would have had to port them), including: - Functions with ARITY > 3 (even 3 isn't used, but just so we don't get complacent) - Variables - Most functions moved out of the header, because only te_interp is used. - The te_print function
2018-10-18 23:00:29 +08:00
// This version was altered and ported to C++ for inclusion in fish.
[tinyexpr] Add error handling This turns a bunch of ifs on their heads. We often see this pattern in te: ```c if (s->type != SOME_TYPE) { // error handling } else { // normal code } ``` Only, since we want to return the first error, we do ```c if (s->type == SOME_TYPE) { // normal code } else if (s->type != TOK_ERROR) { // Add a new error - if it already has type error // this should already be handled. } ``` One big issue is the comma operator, that means arity-1 functions can take an arbitrary number of arguments. E.g. ```fish math "sin(5,9)" ``` will return the value of sin for _9_, since this is read as "5 COMMA 9".
2018-02-12 07:02:47 +08:00
Replace muparser with tinyexpr
2018-02-11 02:46:34 +08:00
#ifndef __TINYEXPR_H__
#define __TINYEXPR_H__
[tinyexpr] Port to C++ This removes the need to run c-compilation on one file, and allows us to in future c++-ify this a bit. There's a lot of bit-fiddling here that is quite unnecessary, better error-handling would be nice... So far this removes a few more unused things (because I would have had to port them), including: - Functions with ARITY > 3 (even 3 isn't used, but just so we don't get complacent) - Variables - Most functions moved out of the header, because only te_interp is used. - The te_print function
2018-10-18 23:00:29 +08:00
typedef enum {
TE_ERROR_NONE = 0,
TE_ERROR_UNKNOWN_VARIABLE = 1,
TE_ERROR_MISSING_CLOSING_PAREN = 2,
TE_ERROR_MISSING_OPENING_PAREN = 3,
TE_ERROR_TOO_FEW_ARGS = 4,
TE_ERROR_TOO_MANY_ARGS = 5,
TE_ERROR_MISSING_OPERATOR = 6,
TE_ERROR_UNKNOWN = 7
} te_error_type_t;
typedef struct te_error_t {
te_error_type_t type;
int position;
} te_error_t;
Replace muparser with tinyexpr
2018-02-11 02:46:34 +08:00
/* Parses the input expression, evaluates it, and frees it. */
/* Returns NaN on error. */
[tinyexpr] Add error handling This turns a bunch of ifs on their heads. We often see this pattern in te: ```c if (s->type != SOME_TYPE) { // error handling } else { // normal code } ``` Only, since we want to return the first error, we do ```c if (s->type == SOME_TYPE) { // normal code } else if (s->type != TOK_ERROR) { // Add a new error - if it already has type error // this should already be handled. } ``` One big issue is the comma operator, that means arity-1 functions can take an arbitrary number of arguments. E.g. ```fish math "sin(5,9)" ``` will return the value of sin for _9_, since this is read as "5 COMMA 9".
2018-02-12 07:02:47 +08:00
double te_interp(const char *expression, te_error_t *error);
Replace muparser with tinyexpr
2018-02-11 02:46:34 +08:00
#endif /*__TINYEXPR_H__*/
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