B Afxa" @sdZddlZddlZddlmZdddddddddZdd Zeejejej ej ej d Z d d d d dZ GdddZedddfddZdS)z pint.pint_eval ~~~~~~~~~~~~~~ An expression evaluator to be used as a safe replacement for builtin eval. :copyright: 2016 by Pint Authors, see AUTHORS for more details. :license: BSD, see LICENSE for more details. N)DefinitionSyntaxError)z**^unary*/+-cCsVddlm}ddlm}t||rJ||jrJ|jjdkrJ|dkrJ|t }t ||S)Nr) is_duck_array)QuantityZcfr) compatr Zquantityr isinstanceZ magnitudeZdtypekindZastypefloatoperatorpow)leftrightr rr-lib/python3.7/site-packages/pint/pint_eval.py_powers      r)z**rr r r r cCs|S)Nr)xrrr5rcCs|dS)Nr)rrrrr5r)r r c@s,eZdZdZd ddZddZd ddZdS) EvalTreeNodezSingle node within an evaluation tree left + operator + right --> binary op left + operator --> unary op left + right --> implicit op left --> single value NcCs||_||_||_dS)N)rrr)selfrrrrrr__init__AszEvalTreeNode.__init__cCsn|jr:|jg}|jr(||jd||jn&|jrV|jd|jg}n |jdSdd|S)Nrz(%s) )rr to_stringrappendjoin)rcompsrrrr"Fs  zEvalTreeNode.to_stringcCs|pt}|pt}|jrh|jr&|jdnd}||kr>td||j|||}||||j|||S|jr|jd}||krtd||||j|||S||jSdS)a_Evaluate node. Parameters ---------- define_op : callable Translates tokens into objects. bin_op : dict or None, optional (Default value = _BINARY_OPERATOR_MAP) un_op : dict or None, optional (Default value = _UNARY_OPERATOR_MAP) Returns ------- rr zmissing binary operator "%s"zmissing unary operator "%s"N)_BINARY_OPERATOR_MAP_UNARY_OPERATOR_MAPrrrrevaluate)rZ define_opZbin_opZun_opZop_textrrrrr(Ss   zEvalTreeNode.evaluate)NN)NN)__name__ __module__ __qualname____doc__r r"r(rrrrr8s  rc Cs>|dkr|dkrt|}d}x||}|d}|d}|tjkrb|dkr|dkrbtd|n|dkrr||fS||dfSn|dkrt|||dd|\} }||ddkstd|rt|| d}n| }n||kr|r8||||d kr |d kr ||dfSt|||d|d|\} }t||| d }n(t|||d|dd \} }t| |d }np|tjksz|tjkr|r|d||d kr||dfSt||||dd\} }t|| d}n t|d}||dtj kr|dkrtd|dks|r||fS|S|dt |kr.td|d7}q WdS)a6Build an evaluation tree from a set of tokens. Params: Index, depth, and prev_op used recursively, so don't touch. Tokens is an iterable of tokens from an expression to be evaluated. Transform the tokens from an expression into a recursive parse tree, following order of operations. Operations can include binary ops (3 + 4), implicit ops (3 kg), or unary ops (-1). General Strategy: 1) Get left side of operator 2) If no tokens left, return final result 3) Get operator 4) Use recursion to create tree starting at token on right side of operator (start at step #1) 4.1) If recursive call encounters an operator with lower or equal priority to step #2, exit recursion 5) Combine left side, operator, and right side into a new left side 6) Go back to step #2 rNr)z"unopened parentheses in tokens: %s(zweird exit from parentheses)rrr)z**r)rrrr)rrr )rzunclosed parentheses in tokenszunexpected end to tokens) listtokenlibOPrbuild_eval_treergetNUMBERNAME ENDMARKERlen) tokensZ op_priorityindexdepthZprev_opresult current_token token_typeZ token_textrrrrr2ysj          r2)r,rtokenr0errorsrZ _OP_PRIORITYrmultruedivaddsubr&r'rr2rrrr s*  A