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SimpleArithmeticParser.ipynb -- A Demo Parser written in python3
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SimpleArithmeticParser.ipynb
{
"cells": [
{
"metadata": {},
"cell_type": "markdown",
"source": "# Simple Arithmetic Parser -- A Parser Demo\n\n## The Parser\n\nThis is a notebook illustrating how a computer program can parse and evaluate simple arithmetic expression.\n\nYou may use the source code under the terms of the GNU General Public License v3 (see the bottom of this notebook)."
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"cell_type": "code",
"source": "# Copyright (c) 2018 Daniel Knüttel #\n# #\n# This program is free software: you can redistribute it and/or modify #\n# it under the terms of the GNU General Public License as published by #\n# the Free Software Foundation, either version 3 of the License, or #\n# (at your option) any later version. #\n# #\n# This program is distributed in the hope that it will be useful, #\n# but WITHOUT ANY WARRANTY; without even the implied warranty of #\n# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #\n# GNU General Public License for more details. #\n# #\n# You should have received a copy of the GNU General Public License #\n# along with this program. If not, see <http://www.gnu.org/licenses/>. #\n# #\n\n\n\n\nfrom collections import deque\nimport string\n\nTOKENS_OPERATOR = [\"+\", \"*\", \"/\", \"-\", \"^\"]\nTOKENS_VARIABLES = string.ascii_letters\n\nclass ParsingException(Exception):\n pass\n\n\n \ndef get_next_parsed_element(element):\n if(not isinstance(element, deque)):\n return element\n else:\n return [get_next_parsed_element(i) for i in element]\n\nclass SimpleArithmethicParser(object):\n \"\"\"\n A parser for simple arithmetic expressions. It is capable of parsing \n binary operators (``TOKENS_OPERATOR``), numbers (of type int), single character\n variables and parenthesis.\n \n It uses a stack to parse parenthesis.\n \"\"\"\n def __init__(self, text):\n self.parsed_list = deque()\n self.text = text\n self._current_stack = deque()\n self._index = 0\n self._state = -1\n self._parsed = False\n self.variables = deque()\n def get_next_char(self):\n char = self.text[self._index]\n self._index += 1\n return char\n def unput_chars(self, chars):\n self._index -= len(chars)\n \n \n def parse_next(self):\n \"\"\"\n Parse the next expression.\n \"\"\"\n next_char = self.get_next_char()\n while(next_char.isspace()):\n next_char = self.get_next_char()\n if(next_char in string.digits):\n chars = next_char\n index_error = None\n try:\n next_char = self.get_next_char()\n while(next_char in string.digits):\n chars += next_chars\n next_char = self.get_next_char()\n except IndexError as e:\n index_error = e\n self.unput_chars(next_char)\n self.parsed_list.append(int(chars))\n self._state = 1\n if(index_error):\n raise index_error\n elif next_char in TOKENS_OPERATOR:\n if(self._state != 1):\n raise ParsingException(\"unexpected token: operator\")\n self.parsed_list.append(next_char)\n self.state = 0\n elif next_char == \"(\":\n self._current_stack.appendleft(self.parsed_list)\n self._state = 2\n self.parsed_list = deque()\n elif next_char == \")\":\n if(self._state == 2):\n raise ParsingException(\"empty parenthesis\")\n if(not self._current_stack):\n raise ParsingException(\"unexpected token: )\")\n self.state = 1\n this_list = self.parsed_list\n self.parsed_list = self._current_stack.popleft()\n self.parsed_list.append(this_list)\n elif(next_char in TOKENS_VARIABLES):\n self.parsed_list.append(next_char)\n if(not next_char in self.variables):\n self.variables.append(next_char)\n self._state = 1\n \n def parse(self):\n \"\"\"\n Parse the entire string.\n \"\"\"\n self._parsed = True\n try:\n while(1):\n self.parse_next()\n except IndexError:\n pass\n if(self._current_stack):\n raise ParsingException(\"unclosed parenthesis\")\n \n def get_list(self):\n \"\"\"\n Return a (nested) list representation of the parsed string.\n If the string is not yet parsed, parse it.\n \"\"\"\n if(not self._parsed):\n self.parse()\n \n return [get_next_parsed_element(i) for i in self.parsed_list]\n \n\n def get_variables(self):\n \"\"\"\n Return a list of variables used in the expression.\n \"\"\"\n return list(sorted(self.variables))\n",
"execution_count": 1,
"outputs": []
},
{
"metadata": {},
"cell_type": "markdown",
"source": "## Some Tests"
},
{
"metadata": {
"trusted": true
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"cell_type": "code",
"source": "parser = SimpleArithmethicParser(\"2 + 3\")\nparser.get_list()",
"execution_count": 2,
"outputs": [
{
"output_type": "execute_result",
"data": {
"text/plain": "[2, '+', 3]"
},
"metadata": {},
"execution_count": 2
}
]
},
{
"metadata": {
"trusted": true
},
"cell_type": "code",
"source": "parser = SimpleArithmethicParser(\"2 + 3 * 5\")\nparser.get_list()",
"execution_count": 3,
"outputs": [
{
"output_type": "execute_result",
"data": {
"text/plain": "[2, '+', 3, '*', 5]"
},
"metadata": {},
"execution_count": 3
}
]
},
{
"metadata": {
"trusted": true
},
"cell_type": "code",
"source": "parser = SimpleArithmethicParser(\"2 + (3 * 5)\")\nparser.get_list()",
"execution_count": 4,
"outputs": [
{
"output_type": "execute_result",
"data": {
"text/plain": "[2, '+', [3, '*', 5]]"
},
"metadata": {},
"execution_count": 4
}
]
},
{
"metadata": {},
"cell_type": "markdown",
"source": "## Cleaning up the Mess\n\nThis function adds the missing _dot_ operators between parenthesis and variables."
},
{
"metadata": {
"trusted": true
},
"cell_type": "code",
"source": "def insert_missing_operators(expression):\n result = deque()\n for i, token in enumerate(expression[:-1]):\n if(isinstance(token, list)):\n token = insert_missing_operators(token)\n result.append(token)\n if(not token in TOKENS_OPERATOR):\n if(expression[i + 1] not in TOKENS_OPERATOR):\n result.append(\"*\")\n if(isinstance(expression[-1], list)):\n result.append(insert_missing_operators(expression[-1]))\n else:\n result.append(expression[-1])\n return list(result)",
"execution_count": 5,
"outputs": []
},
{
"metadata": {},
"cell_type": "markdown",
"source": "## An Executor\n\nThis functions adds an evaluator. They produce a function that takes exactly the number of\nvariables as arguments and evaluates the expression. It respects calculation rules (like dot before slash).\n\nThe arguments must be given in alphabetic order (**not in the order they appear**)."
},
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"metadata": {
"trusted": true
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"cell_type": "code",
"source": "\noperator_to_function = {\n\"*\": lambda a,b : a * b,\n\"+\": lambda a,b : a + b,\n\"-\": lambda a,b : a - b,\n\"/\": lambda a,b : a / b,\n\"^\": lambda a,b : a ** b\n}\n\noperator_to_priority = {\n\"+\": 0,\n\"-\": 0,\n\"*\": 1,\n\"/\": 1,\n\"^\": 2\n}\n\n\ndef eval_next(expression_left, variables_to_args):\n \n # this is for a + b * c\n if(len(expression_left) == 1):\n exp = expression_left[0]\n if(exp in variables_to_args):\n return variables_to_args\n return exp\n \n a, op, b = expression_left[:3]\n\n if(isinstance(a, list)):\n a = eval_next(a, variables_to_args)\n if(isinstance(b, list)):\n b = eval_next(b, variables_to_args)\n \n if(a in variables_to_args):\n a = variables_to_args[a]\n if(b in variables_to_args):\n b = variables_to_args[b]\n \n if(len(expression_left) > 3):\n next_op = expression_left[3]\n \n if(operator_to_priority[next_op] > operator_to_priority[op]):\n return operator_to_function[op](a, eval_next(expression_left[2:], variables_to_args))\n else:\n return eval_next([operator_to_function[op](a, b)] + expression_left[3:], variables_to_args)\n return operator_to_function[op](a, b)\n \n \n \ndef make_function(parser):\n \n variables = parser.get_variables()\n expression = insert_missing_operators(parser.get_list())\n \n def f(*args):\n if(len(args) != len(variables)):\n raise TypeError(\"f takes {} positional arguments but {} were given\".format(\n len(variables), len(args)))\n variables_to_args = {k:v for k,v in zip(variables, args)}\n return eval_next(expression, variables_to_args)\n\n return f \n \n \n ",
"execution_count": 6,
"outputs": []
},
{
"metadata": {
"trusted": true
},
"cell_type": "code",
"source": "f = make_function(parser)\nf()",
"execution_count": 7,
"outputs": [
{
"output_type": "execute_result",
"data": {
"text/plain": "17"
},
"metadata": {},
"execution_count": 7
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]
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"metadata": {
"trusted": true
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"cell_type": "code",
"source": "parser = SimpleArithmethicParser(\"(x + y) * 2\")\nparser.parse()\nf = make_function(parser)\n\nf(2, 3)",
"execution_count": 8,
"outputs": [
{
"output_type": "execute_result",
"data": {
"text/plain": "10"
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"metadata": {},
"execution_count": 8
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"metadata": {},
"cell_type": "markdown",
"source": "## GNU GENERAL PUBLIC LICENSE\n\nVersion 3, 29 June 2007\n\nCopyright (C) 2007 Free Software Foundation, Inc.\n<https://fsf.org/>\n\nEveryone is permitted to copy and distribute verbatim copies of this\nlicense document, but changing it is not allowed.\n\n### Preamble\n\nThe GNU General Public License is a free, copyleft license for\nsoftware and other kinds of works.\n\nThe licenses for most software and other practical works are designed\nto take away your freedom to share and change the works. By contrast,\nthe GNU General Public License is intended to guarantee your freedom\nto share and change all versions of a program--to make sure it remains\nfree software for all its users. We, the Free Software Foundation, use\nthe GNU General Public License for most of our software; it applies\nalso to any other work released this way by its authors. You can apply\nit to your programs, too.\n\nWhen we speak of free software, we are referring to freedom, not\nprice. Our General Public Licenses are designed to make sure that you\nhave the freedom to distribute copies of free software (and charge for\nthem if you wish), that you receive source code or can get it if you\nwant it, that you can change the software or use pieces of it in new\nfree programs, and that you know you can do these things.\n\nTo protect your rights, we need to prevent others from denying you\nthese rights or asking you to surrender the rights. Therefore, you\nhave certain responsibilities if you distribute copies of the\nsoftware, or if you modify it: responsibilities to respect the freedom\nof others.\n\nFor example, if you distribute copies of such a program, whether\ngratis or for a fee, you must pass on to the recipients the same\nfreedoms that you received. You must make sure that they, too, receive\nor can get the source code. And you must show them these terms so they\nknow their rights.\n\nDevelopers that use the GNU GPL protect your rights with two steps:\n(1) assert copyright on the software, and (2) offer you this License\ngiving you legal permission to copy, distribute and/or modify it.\n\nFor the developers' and authors' protection, the GPL clearly explains\nthat there is no warranty for this free software. For both users' and\nauthors' sake, the GPL requires that modified versions be marked as\nchanged, so that their problems will not be attributed erroneously to\nauthors of previous versions.\n\nSome devices are designed to deny users access to install or run\nmodified versions of the software inside them, although the\nmanufacturer can do so. This is fundamentally incompatible with the\naim of protecting users' freedom to change the software. The\nsystematic pattern of such abuse occurs in the area of products for\nindividuals to use, which is precisely where it is most unacceptable.\nTherefore, we have designed this version of the GPL to prohibit the\npractice for those products. If such problems arise substantially in\nother domains, we stand ready to extend this provision to those\ndomains in future versions of the GPL, as needed to protect the\nfreedom of users.\n\nFinally, every program is threatened constantly by software patents.\nStates should not allow patents to restrict development and use of\nsoftware on general-purpose computers, but in those that do, we wish\nto avoid the special danger that patents applied to a free program\ncould make it effectively proprietary. To prevent this, the GPL\nassures that patents cannot be used to render the program non-free.\n\nThe precise terms and conditions for copying, distribution and\nmodification follow.\n\n### TERMS AND CONDITIONS\n\n#### 0. Definitions.\n\n\"This License\" refers to version 3 of the GNU General Public License.\n\n\"Copyright\" also means copyright-like laws that apply to other kinds\nof works, such as semiconductor masks.\n\n\"The Program\" refers to any copyrightable work licensed under this\nLicense. Each licensee is addressed as \"you\". \"Licensees\" and\n\"recipients\" may be individuals or organizations.\n\nTo \"modify\" a work means to copy from or adapt all or part of the work\nin a fashion requiring copyright permission, other than the making of\nan exact copy. 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But this requirement does not apply\nif neither you nor any third party retains the ability to install\nmodified object code on the User Product (for example, the work has\nbeen installed in ROM).\n\nThe requirement to provide Installation Information does not include a\nrequirement to continue to provide support service, warranty, or\nupdates for a work that has been modified or installed by the\nrecipient, or for the User Product in which it has been modified or\ninstalled. Access to a network may be denied when the modification\nitself materially and adversely affects the operation of the network\nor violates the rules and protocols for communication across the\nnetwork.\n\nCorresponding Source conveyed, and Installation Information provided,\nin accord with this section must be in a format that is publicly\ndocumented (and with an implementation available to the public in\nsource code form), and must require no special password or key for\nunpacking, reading or copying.\n\n#### 7. Additional Terms.\n\n\"Additional permissions\" are terms that supplement the terms of this\nLicense by making exceptions from one or more of its conditions.\nAdditional permissions that are applicable to the entire Program shall\nbe treated as though they were included in this License, to the extent\nthat they are valid under applicable law. If additional permissions\napply only to part of the Program, that part may be used separately\nunder those permissions, but the entire Program remains governed by\nthis License without regard to the additional permissions.\n\nWhen you convey a copy of a covered work, you may at your option\nremove any additional permissions from that copy, or from any part of\nit. (Additional permissions may be written to require their own\nremoval in certain cases when you modify the work.) You may place\nadditional permissions on material, added by you to a covered work,\nfor which you have or can give appropriate copyright permission.\n\nNotwithstanding any other provision of this License, for material you\nadd to a covered work, you may (if authorized by the copyright holders\nof that material) supplement the terms of this License with terms:\n\n- a) Disclaiming warranty or limiting liability differently from the\n terms of sections 15 and 16 of this License; or\n- b) Requiring preservation of specified reasonable legal notices or\n author attributions in that material or in the Appropriate Legal\n Notices displayed by works containing it; or\n- c) Prohibiting misrepresentation of the origin of that material,\n or requiring that modified versions of such material be marked in\n reasonable ways as different from the original version; or\n- d) Limiting the use for publicity purposes of names of licensors\n or authors of the material; or\n- e) Declining to grant rights under trademark law for use of some\n trade names, trademarks, or service marks; or\n- f) Requiring indemnification of licensors and authors of that\n material by anyone who conveys the material (or modified versions\n of it) with contractual assumptions of liability to the recipient,\n for any liability that these contractual assumptions directly\n impose on those licensors and authors.\n\nAll other non-permissive additional terms are considered \"further\nrestrictions\" within the meaning of section 10. If the Program as you\nreceived it, or any part of it, contains a notice stating that it is\ngoverned by this License along with a term that is a further\nrestriction, you may remove that term. If a license document contains\na further restriction but permits relicensing or conveying under this\nLicense, you may add to a covered work material governed by the terms\nof that license document, provided that the further restriction does\nnot survive such relicensing or conveying.\n\nIf you add terms to a covered work in accord with this section, you\nmust place, in the relevant source files, a statement of the\nadditional terms that apply to those files, or a notice indicating\nwhere to find the applicable terms.\n\nAdditional terms, permissive or non-permissive, may be stated in the\nform of a separately written license, or stated as exceptions; the\nabove requirements apply either way.\n\n#### 8. Termination.\n\nYou may not propagate or modify a covered work except as expressly\nprovided under this License. Any attempt otherwise to propagate or\nmodify it is void, and will automatically terminate your rights under\nthis License (including any patent licenses granted under the third\nparagraph of section 11).\n\nHowever, if you cease all violation of this License, then your license\nfrom a particular copyright holder is reinstated (a) provisionally,\nunless and until the copyright holder explicitly and finally\nterminates your license, and (b) permanently, if the copyright holder\nfails to notify you of the violation by some reasonable means prior to\n60 days after the cessation.\n\nMoreover, your license from a particular copyright holder is\nreinstated permanently if the copyright holder notifies you of the\nviolation by some reasonable means, this is the first time you have\nreceived notice of violation of this License (for any work) from that\ncopyright holder, and you cure the violation prior to 30 days after\nyour receipt of the notice.\n\nTermination of your rights under this section does not terminate the\nlicenses of parties who have received copies or rights from you under\nthis License. If your rights have been terminated and not permanently\nreinstated, you do not qualify to receive new licenses for the same\nmaterial under section 10.\n\n#### 9. Acceptance Not Required for Having Copies.\n\nYou are not required to accept this License in order to receive or run\na copy of the Program. Ancillary propagation of a covered work\noccurring solely as a consequence of using peer-to-peer transmission\nto receive a copy likewise does not require acceptance. However,\nnothing other than this License grants you permission to propagate or\nmodify any covered work. These actions infringe copyright if you do\nnot accept this License. Therefore, by modifying or propagating a\ncovered work, you indicate your acceptance of this License to do so.\n\n#### 10. Automatic Licensing of Downstream Recipients.\n\nEach time you convey a covered work, the recipient automatically\nreceives a license from the original licensors, to run, modify and\npropagate that work, subject to this License. You are not responsible\nfor enforcing compliance by third parties with this License.\n\nAn \"entity transaction\" is a transaction transferring control of an\norganization, or substantially all assets of one, or subdividing an\norganization, or merging organizations. If propagation of a covered\nwork results from an entity transaction, each party to that\ntransaction who receives a copy of the work also receives whatever\nlicenses to the work the party's predecessor in interest had or could\ngive under the previous paragraph, plus a right to possession of the\nCorresponding Source of the work from the predecessor in interest, if\nthe predecessor has it or can get it with reasonable efforts.\n\nYou may not impose any further restrictions on the exercise of the\nrights granted or affirmed under this License. For example, you may\nnot impose a license fee, royalty, or other charge for exercise of\nrights granted under this License, and you may not initiate litigation\n(including a cross-claim or counterclaim in a lawsuit) alleging that\nany patent claim is infringed by making, using, selling, offering for\nsale, or importing the Program or any portion of it.\n\n#### 11. Patents.\n\nA \"contributor\" is a copyright holder who authorizes use under this\nLicense of the Program or a work on which the Program is based. The\nwork thus licensed is called the contributor's \"contributor version\".\n\nA contributor's \"essential patent claims\" are all patent claims owned\nor controlled by the contributor, whether already acquired or\nhereafter acquired, that would be infringed by some manner, permitted\nby this License, of making, using, or selling its contributor version,\nbut do not include claims that would be infringed only as a\nconsequence of further modification of the contributor version. For\npurposes of this definition, \"control\" includes the right to grant\npatent sublicenses in a manner consistent with the requirements of\nthis License.\n\nEach contributor grants you a non-exclusive, worldwide, royalty-free\npatent license under the contributor's essential patent claims, to\nmake, use, sell, offer for sale, import and otherwise run, modify and\npropagate the contents of its contributor version.\n\nIn the following three paragraphs, a \"patent license\" is any express\nagreement or commitment, however denominated, not to enforce a patent\n(such as an express permission to practice a patent or covenant not to\nsue for patent infringement). To \"grant\" such a patent license to a\nparty means to make such an agreement or commitment not to enforce a\npatent against the party.\n\nIf you convey a covered work, knowingly relying on a patent license,\nand the Corresponding Source of the work is not available for anyone\nto copy, free of charge and under the terms of this License, through a\npublicly available network server or other readily accessible means,\nthen you must either (1) cause the Corresponding Source to be so\navailable, or (2) arrange to deprive yourself of the benefit of the\npatent license for this particular work, or (3) arrange, in a manner\nconsistent with the requirements of this License, to extend the patent\nlicense to downstream recipients. \"Knowingly relying\" means you have\nactual knowledge that, but for the patent license, your conveying the\ncovered work in a country, or your recipient's use of the covered work\nin a country, would infringe one or more identifiable patents in that\ncountry that you have reason to believe are valid.\n\nIf, pursuant to or in connection with a single transaction or\narrangement, you convey, or propagate by procuring conveyance of, a\ncovered work, and grant a patent license to some of the parties\nreceiving the covered work authorizing them to use, propagate, modify\nor convey a specific copy of the covered work, then the patent license\nyou grant is automatically extended to all recipients of the covered\nwork and works based on it.\n\nA patent license is \"discriminatory\" if it does not include within the\nscope of its coverage, prohibits the exercise of, or is conditioned on\nthe non-exercise of one or more of the rights that are specifically\ngranted under this License. You may not convey a covered work if you\nare a party to an arrangement with a third party that is in the\nbusiness of distributing software, under which you make payment to the\nthird party based on the extent of your activity of conveying the\nwork, and under which the third party grants, to any of the parties\nwho would receive the covered work from you, a discriminatory patent\nlicense (a) in connection with copies of the covered work conveyed by\nyou (or copies made from those copies), or (b) primarily for and in\nconnection with specific products or compilations that contain the\ncovered work, unless you entered into that arrangement, or that patent\nlicense was granted, prior to 28 March 2007.\n\nNothing in this License shall be construed as excluding or limiting\nany implied license or other defenses to infringement that may\notherwise be available to you under applicable patent law.\n\n#### 12. No Surrender of Others' Freedom.\n\nIf conditions are imposed on you (whether by court order, agreement or\notherwise) that contradict the conditions of this License, they do not\nexcuse you from the conditions of this License. If you cannot convey a\ncovered work so as to satisfy simultaneously your obligations under\nthis License and any other pertinent obligations, then as a\nconsequence you may not convey it at all. For example, if you agree to\nterms that obligate you to collect a royalty for further conveying\nfrom those to whom you convey the Program, the only way you could\nsatisfy both those terms and this License would be to refrain entirely\nfrom conveying the Program.\n\n#### 13. Use with the GNU Affero General Public License.\n\nNotwithstanding any other provision of this License, you have\npermission to link or combine any covered work with a work licensed\nunder version 3 of the GNU Affero General Public License into a single\ncombined work, and to convey the resulting work. The terms of this\nLicense will continue to apply to the part which is the covered work,\nbut the special requirements of the GNU Affero General Public License,\nsection 13, concerning interaction through a network will apply to the\ncombination as such.\n\n#### 14. Revised Versions of this License.\n\nThe Free Software Foundation may publish revised and/or new versions\nof the GNU General Public License from time to time. Such new versions\nwill be similar in spirit to the present version, but may differ in\ndetail to address new problems or concerns.\n\nEach version is given a distinguishing version number. If the Program\nspecifies that a certain numbered version of the GNU General Public\nLicense \"or any later version\" applies to it, you have the option of\nfollowing the terms and conditions either of that numbered version or\nof any later version published by the Free Software Foundation. If the\nProgram does not specify a version number of the GNU General Public\nLicense, you may choose any version ever published by the Free\nSoftware Foundation.\n\nIf the Program specifies that a proxy can decide which future versions\nof the GNU General Public License can be used, that proxy's public\nstatement of acceptance of a version permanently authorizes you to\nchoose that version for the Program.\n\nLater license versions may give you additional or different\npermissions. However, no additional obligations are imposed on any\nauthor or copyright holder as a result of your choosing to follow a\nlater version.\n\n#### 15. Disclaimer of Warranty.\n\nTHERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY\nAPPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT\nHOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM \"AS IS\" WITHOUT\nWARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT\nLIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR\nA PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND\nPERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE\nDEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR\nCORRECTION.\n\n#### 16. Limitation of Liability.\n\nIN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING\nWILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR\nCONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,\nINCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES\nARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT\nNOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR\nLOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM\nTO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER\nPARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.\n\n#### 17. Interpretation of Sections 15 and 16.\n\nIf the disclaimer of warranty and limitation of liability provided\nabove cannot be given local legal effect according to their terms,\nreviewing courts shall apply local law that most closely approximates\nan absolute waiver of all civil liability in connection with the\nProgram, unless a warranty or assumption of liability accompanies a\ncopy of the Program in return for a fee.\n\nEND OF TERMS AND CONDITIONS\n\n"
},
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"description": "SimpleArithmeticParser.ipynb -- A Demo Parser written in python3",
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"hotkey": "alt-t",
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"varInspector": {
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"kernels_config": {
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"delete_cmd_prefix": "del ",
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