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Tcl - Relational Operators
Following table shows all the relational operators supported by Tcl language. Assume variable A holds 10 and variable B holds 20, then −
Operator | Description | Example |
---|---|---|
== | Checks if the values of two operands are equal or not, if yes then condition becomes true. | (A == B) is not true. |
!= | Checks if the values of two operands are equal or not, if values are not equal then condition becomes true. | (A != B) is true. |
> | Checks if the value of left operand is greater than the value of right operand, if yes then condition becomes true. | (A > B) is not true. |
< | Checks if the value of left operand is less than the value of right operand, if yes then condition becomes true. | (A < B) is true. |
>= | Checks if the value of left operand is greater than or equal to the value of right operand, if yes then condition becomes true. | (A >= B) is not true. |
<= | Checks if the value of left operand is less than or equal to the value of right operand, if yes then condition becomes true. | (A <= B) is true. |
Example
Try the following example to understand all the relational operators available in Tcl language −
#!/usr/bin/tclsh set a 21 set b 10 if { $a == $b } { puts "Line 1 - a is equal to b\n" } else { puts "Line 1 - a is not equal to b\n" } if { $a < $b } { puts "Line 2 - a is less than b\n" } else { puts "Line 2 - a is not less than b\n" } if { $a > $b } { puts "Line 3 - a is greater than b\n" } else { puts "Line 3 - a is not greater than b\n" } # Lets change value of a and b set a 5 set b 20 if { $a <= $b } { puts "Line 4 - a is either less than or equal to b\n" } if { $b >= $a } { puts "Line 5 - b is either greater than or equal to a\n" }
When you compile and execute the above program it produces the following result −
Line 1 - a is not equal to b Line 2 - a is not less than b Line 3 - a is greater than b Line 4 - a is either less than or equal to b Line 5 - b is either greater than or equal to a
tcl_operators.htm
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