Call By Reference: Difference between revisions
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Call By Reference is a technique where arguments that are passed into a procedure or function are the actual memory resident values from the calling procedure. When the value of an argument passed by reference is changed in the child procedure, the value of the argument in the parent procedure is also changed, since technically they are the same arguement. | '''Call By Reference''' or '''Pass By Reference''' is a technique where arguments that are passed into a [[procedure]] or [[function]] are the actual memory resident values from the calling procedure. When the value of an argument passed by reference is changed in the child procedure, the value of the argument in the parent procedure is also changed, since technically they are the same arguement. | ||
==Example== | ==Example== | ||
The following code passes a reference to the argument ''sName'' in to the procedure '''DoCall'''. | The following code passes a reference to the argument ''sName'' in to the procedure '''DoCall'''. | ||
< | <source lang="dataflex"> | ||
String sName | String sName | ||
| Line 15: | Line 15: | ||
Send DoCall(&sName) | Send DoCall(&sName) | ||
showln "name:" sName | showln "name:" sName | ||
</ | </source> | ||
The output window would display: | The output window would display: | ||
Latest revision as of 11:11, 24 February 2019
Call By Reference or Pass By Reference is a technique where arguments that are passed into a procedure or function are the actual memory resident values from the calling procedure. When the value of an argument passed by reference is changed in the child procedure, the value of the argument in the parent procedure is also changed, since technically they are the same arguement.
Example
The following code passes a reference to the argument sName in to the procedure DoCall.
String sName
Procedure DoCall String ByRef sName
showln "name:" sName
Move "B" to sName
End_Procedure
Move "A" to sName
Send DoCall(&sName)
showln "name:" sName
The output window would display:
name:A name:B
