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**BINDEXPRESSION( **| //name,expression //| **)**

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| **BINDEXPRESSION** | Identifies variables allowed to be used in dynamic expressions. |
| //name// | A string constant containing the identifier used in the dynamic expression. |
| //expression// | A mathematical formula containing any valid combination of variables, functions, operators, and constants. |

The **BINDEXPRESSION** statement declares the logical name used to identify an expression used in runtime expression strings.

The **EVALUATE** statement must parse an expression every time it is called. If some expression is evaluated frequently, this can be time consuming.

**BINDEXPRESSION** parses the expression only once and is saved in a pre-compiled form under the given //name//. Later, this expression can be used in EVALUATE as a stand alone, or as a part of another expression in EVALUATE, or in another BINDEXPRESSION.

**Example:**

**  BIND('Var', Var)**

** ****BINDEXPRESSION****('Power2', 'Var * Var')**

**  ...**

**  Var = 10**

**  P2  = EVALUATE ('Power2')**

**  ...**

** ****BINDEXPRESSION**** ('Circle', '3.14159 * Power2')**

** ****BINDEXPRESSION****('color:red',color:red)**

**  MESSAGE('color:red = ' & color:red & '|Eval(color:red)=' &|**

**  EVALUATE('color:red') )        !Shows same number twice**

** ****BINDEXPRESSION****('Match:Soundex',Match:Soundex)**

**  FILTER('MATCH(Cus:Name,NameWanted,Match:Soundex)')**

**See Also:**

[[bind  declare runtime expression string variable .htm|BIND (declare runtime expression string variable)]]

[[evaluate  return runtime expression string result .htm|EVALUATE (return runtime expression string result)]]