This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.1)

SyntaxQ

SyntaxQ
returns True if the string corresponds to syntactically correct input for a single Mathematica expression, and returns False otherwise.
Test if a string is valid Mathematica syntax:
When SyntaxQ gives True, the string can be converted to an expression:
Request input from a dialog repeatedly until it is syntactically correct:
Test if a string is valid Mathematica syntax:
In[1]:=
Click for copyable input
Out[1]=
In[2]:=
Click for copyable input
Out[2]=
When SyntaxQ gives True, the string can be converted to an expression:
In[3]:=
Click for copyable input
Out[3]=
 
Request input from a dialog repeatedly until it is syntactically correct:
In[1]:=
Click for copyable input
Out[1]=
New in 2