Assignment Operations: Difference between revisions
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[[Numeric]] and [[String]] [[Variable|variables]] both may be used with regular and forced assignment operators. | [[Numeric]] and [[String]] [[Variable|variables]] both may be used with regular and forced assignment operators. | ||
==Regular Assignment== | ===Regular Assignment=== | ||
The equal sign '''=''' simply makes the variable on the left side of it equal to the value on the right side of it. The example below assigns the value of 5 to the variable x: | The equal sign '''=''' simply makes the variable on the left side of it equal to the value on the right side of it. The example below assigns the value of 5 to the variable x: | ||
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The disadvantage of the equal sign assignment operator '''=''' is that it may only be used as a separate statement. | The disadvantage of the equal sign assignment operator '''=''' is that it may only be used as a separate statement. | ||
==Forced Assignment== | ===Forced Assignment=== | ||
If your programming needs call for multiple operations in one statement, you may use the '''forced assignment''' operator ''':='''. The example below assigns the value of 5 to x and then compares the value of x (which is now 5) to the value of 2: | If your programming needs call for multiple operations in one statement, you may use the '''forced assignment''' operator ''':='''. The example below assigns the value of 5 to x and then compares the value of x (which is now 5) to the value of 2: |
Revision as of 17:09, 10 January 2012
There are two assignment operators in BR: the equal sign =, which denotes regular assignment, and the colon-equal sign :=, which denotes forced assignment,
They are similar in how they work with a slight difference.
Both of them are Binary operators, which means they take two arguments - one on the left, and another one on the right.
Numeric and String variables both may be used with regular and forced assignment operators.
Regular Assignment
The equal sign = simply makes the variable on the left side of it equal to the value on the right side of it. The example below assigns the value of 5 to the variable x:
00010 let x = 5 ! correct
Note that you cannot do the reverse. The example below will result in an error.
00010 let 5 = x ! incorrect
The disadvantage of the equal sign assignment operator = is that it may only be used as a separate statement.
Forced Assignment
If your programming needs call for multiple operations in one statement, you may use the forced assignment operator :=. The example below assigns the value of 5 to x and then compares the value of x (which is now 5) to the value of 2:
00010 if (x:=5) > 2 then print "The forced-assigned value is larger than 2"
Note that when this assignment operator is used in any expression (for example: in the condition of an IF THEN statement), parentheses must be used to clarify the order of execution Otherwise, unexpected results may occur.