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--- syntax:functions:eval [2020/07/08 18:03] – dmitry
+++ syntax:functions:eval [2021/09/13 21:03] – craigt
@@ Line 1: / Line 1: @@
-===== Eval(text) =====
+====== Eval(text_expression) ======
+Category:  Special function
-Evaluates the text argument as an EasyMorph expression. The argument itself must not be
+\\
-an expression with a reference to column.
+=====Description=====
+This function evaluates the //text_expression// argument as an EasyMorph expression.
-Examples:
+\\
+=====Use cases=====
+This function makes it possible to define EasyMorph expressions externally using parameters.
-    eval('1+1')           //Result is 2.
+\\
+=====Arguments=====
+^Argument^Type^Description^
+|text_expression|Text|An expression in text format to be evaluated.|
+**Return value type:** Any (The type of the expression output)
+\\
+=====Remarks=====
+The argument itself must not be an expression with a reference to column.
+\\
+=====Examples=====
+    eval('1+1')  //Returns 2
-    eval('1' & '+1')      //Result is 2.
+    eval('1' & '+1')  //Returns 2
-    eval('max(1,2)')      //Result is 2.
+    eval('max(1,2)')  //Returns 2
-    eval('[Count]+1')     //Evaluated as [Count]+1.
+    eval('[Count]+1')  //Evaluated as [Count]+1
-    eval([Count] & '+1')  //Invalid! References to columns are not allowed in argument expressions.
+    eval([Count] & '+1')  //Invalid! Column references are not allowed in argument expressions.
-    eval({Param1})        //If the value of {Param1} is '[Count]+1' then it's evaluated as [Count]+1. Parameter references are allowed.
+    eval({Param1})  //Parameter references to expressions in text format are allowed.
-The eval() function makes it possible to define EasyMorph expressions externally using parameters.
+    eval("1+" & "eval('1+1')")  //Returns 3  (Nesting eval() is allowed.)