src/main/kotlin/Field.kt

@@ -14,17 +14,19 @@ class Field<T> private constructor(
     val parameterName: String? = null,
     val qualifier: String? = null) {
 
+    init {
+        if (parameterName != null && !parameterName.startsWith(':') && !parameterName.startsWith('@'))
+            throw DocumentException("Parameter Name must start with : or @ ($name)")
+    }
+
     /**
      * Specify the parameter name for the field
      *
      * @param paramName The parameter name to use for this field
      * @return A new `Field` with the parameter name specified
      */
-    fun withParameterName(paramName: String): Field<T> {
+    fun withParameterName(paramName: String) =
-        if (!paramName.startsWith(':') && !paramName.startsWith('@'))
+        Field(name, comparison, paramName, qualifier)
-            throw DocumentException("Parameter must start with : or @ ($paramName)")
-        return Field(name, comparison, paramName, qualifier)
-    }
 
     /**
      * Specify a qualifier (alias) for the document table

src/test/kotlin/FieldTest.kt

@@ -530,6 +530,12 @@ class FieldTest {
         assertNull(field.qualifier, "The qualifier should have been null")
     }
 
+    @Test
+    @DisplayName("static constructors fail for invalid parameter name")
+    fun staticCtorsFailOnParamName() {
+        assertThrows<DocumentException> { Field.equal("a", "b", "that ain't it, Jack...") }
+    }
+
     @Test
     @DisplayName("nameToPath creates a simple PostgreSQL SQL name")
     fun nameToPathPostgresSimpleSQL() =