Built-in Mathematica Symbol

ToExpression

ToExpression[input]
gives the expression obtained by interpreting strings or boxes as Mathematica input.

ToExpression[input, form]
uses interpretation rules corresponding to the specified form.

ToExpression[input, form, h]
wraps the head h around the expression produced before evaluating it.

MORE INFORMATION

form can be InputForm, StandardForm, TeXForm, TraditionalForm or MathMLForm.

ToExpression["string"] uses InputForm interpretation rules.

ToExpression[boxes] uses StandardForm interpretation rules.

ToExpression prints a message and returns $Failed if it finds a syntax error. ToExpression does not call $SyntaxHandler. »

The input given in ToExpression can correspond to multiple Mathematica expressions. ToExpression processes each one in turn, just like Get. »

ToExpression[input, form, Hold] can be used to convert input to an expression, but with the expression wrapped in Hold to prevent evaluation. »

ToExpression uses any relevant definitions given for MakeExpression.

EXAMPLES

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Basic Examples (5)

Convert a string to an expression, and evaluate the expression:

Interpret a TraditionalForm string:

Convert boxes to Mathematica input:

Convert MathML strings to expressions:

Convert

strings to expressions:

Convert a string to an expression, and evaluate the expression:

In[1]:=

Out[1]=

Interpret a TraditionalForm string:

In[1]:=

Out[1]=

Convert boxes to Mathematica input:

In[1]:=

Out[1]=

Convert MathML strings to expressions:

In[1]:=

Out[1]=

Convert

strings to expressions:

In[1]:=

Out[1]=

Scope (2)

Convert a string to an expression using TraditionalForm rules:

Convert the same string using StandardForm and InputForm rules:

Convert and evaluate a string representing multiple lines of code:

Generalizations & Extensions (1)

Apply the head Hold to prevent evaluation:

Properties & Relations (2)

ToExpression evaluates the expression, while MakeExpression does not:

Display an InterpretationBox:

The expression is the second argument of the InterpretationBox:

Possible Issues (1)

Input containing invalid or incomplete syntax cannot be converted to expressions: