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import::readlisp

Parse Lisp-formatted string

Use only in the MuPAD Notebook Interface.

This functionality does not run in MATLAB.

Syntax

import::readlisp(s)

Description

import::readlisp(s) parses the Lisp-formatted string s and returns the corresponding MuPAD® expression.

import::readlisp returns the constructed MuPAD expression as an unevaluated call. So the result of import::readlisp is in every case of type DOM_EXPR.

If the parsed string s contains only white spaces, then the unevaluated null() expression is returned.

Examples

Example 1

A first example:

import::readlisp("(INTEGRATE (EXPT X -1) X)")

import::readlisp("(EXP 2.0)")

Example 2

In Example 1 above we can see that the corresponding MuPAD expression is not evaluated. Let us have a closer look at this behavior:

domtype(import::readlisp("(INTEGRATE (EXPT X -1) X)")),
eval(import::readlisp("(INTEGRATE (EXPT X -1) X)")), 
domtype(import::readlisp("(EXP 2.0)")),
eval(import::readlisp("(EXP 2.0)"))

Example 3

Another example demonstrating that import::readlisp returns an unevaluated call:

x := 2:  import::readlisp("(* x (/ 2 y))")

eval(import::readlisp("(* x (/ 2 y))"))

Example 4

An empty string is converted into an unevaluated call of null():

type(import::readlisp(""))

We try to convert an illegal Lisp string:

import::readlisp("(* 2(EXP 3)")
Error: The closing parenthesis is missing. [import::parseLambda]

Parameters

s

A string

Return Values

MuPAD expression of type DOM_EXPR

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