General Specification Electrical Function gmw3110 General Motors Local Area Network Enhanced Diagnostic Test Mode Specification

GM WORLDWIDE ENGINEERING STANDARDS 
GMW3110 
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February 2010 
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body when second expression is TRUE 
OTHERWISE 
body when all expressions are FALSE 
ENDSELECT 
3.6.2.1.3 Loop Statement. 
Loop statements are useful when it is desirable to execute a body of code in a 
repetitive fashion until an exit criteria is established. This type of statement is typically used when performing 
operations on arrays of data or data structures as it provides an easy mechanism to index through the array. 
Loop statements use the keywords FOR and ENDFOR to mark the beginning and ending points of the loop 
statement. 
Included below is an example of a loop statement: 
FOR (target value1 TO value2 BY value3)
body to be performed for each value 
ENDFOR 
The first time the code encounters the keyword FOR, the variable 
target
is assigned a value defined by 
value1
. On the right of the keyword TO is a variable called 
value2
which is compared with the variable 
target
as a relational expression to determine if it is ok to exit the repetitive task. If the relational expression evaluates 
TRUE, then the body is executed. After executing the body of the loop, the variable 
target
is incremented by 
the value of the variable after the keyword BY (in this case 
value3
) and the relational expression is re-
evaluated. The body will continue to be executed as long as the relational expression evaluates to TRUE. 
Once the relational expression evaluates FALSE, the loop is exited and control continues with the next 
statement after the ENDFOR. 
Note:
The convention used throughout this specification for handling the case where value1 equals value2 is 
that the expression is considered TRUE and the body code shall be executed.