One of the features that Sass provides are equality operators, which are special operators that can be used to compare values and make decisions in your stylesheets.
There are three types of equality operators in Sass: the equal operator, the not equal operator, and the matching operator.
The equal operator
The equal operator (==) is used to check if two values are equal to each other. For example, you could use the equal operator to check if a variable is equal to a specific value:
$color: blue;
body {
color: $color;
}
@if $color == blue {
background-color: blue;
}In this example, the equal operator is used to check if the value of the $color variable is equal to "blue." If it is, the background color of the body element is set to blue.
The not equal operator
The not equal operator (!=) is used to check if two values are not equal to each other. For example, you could use the not equal operator to check if a variable is not equal to a specific value:
$color: blue;
body {
color: $color;
}
@if $color != red {
background-color: blue;
}In this example, the not equal operator is used to check if the value of the $color variable is not equal to "red." If it is not, the background color of the body element is set to blue.
The matching operator (~)
The matching operator (~) is used to check if a string matches a regular expression pattern. For example, you could use the matching operator to check if a variable matches a specific pattern:
$color: blue;
body {
color: $color;
}
@if $color =~ /blu/ {
background-color: blue;
}In this example, the matching operator is used to check if the value of the $color variable matches the regular expression pattern /blu/. If it does, the background color of the body element is set to blue.
Additionally, Sass also provides the not matching operator (!~) which is used to check if a string does not match a regular expression pattern.
$color: blue;
body {
color: $color;
}
@if $color !~ /red/ {
background-color: blue;
}In this example, the not matching operator is used to check if the value of the $color variable does not match the regular expression pattern /red/. If it doesn't, the background color of the body element is set to blue.
It's important to note that all the comparison operators are case-sensitive. So, when comparing strings, they will only return true if they match the case of the string.
Equality operators can be used in conjunction with other Sass features such as control directives like @if and @else to create more complex stylesheets. For example, you could use the equal operator to check if a variable is equal to a specific value and then use the @else directive to specify a different value for the same property if the variable is not equal to the specified value:
$color: blue;
body {
color: $color;
}
@if $color == blue {
background-color: blue;
} @else {
background-color: red;
}In this example, the equal operator is used to check if the value of the $color variable is equal to "blue." If it is, the background color of the body element is set to blue. If it is not, the background color of the body element is set to red.
Equality operators can also be used in conjunction with loops and iteration. For example, you could use the equal operator to check if a variable is equal to a specific value and then use a loop to iterate through a list of values and output a different value for the same property for each value in the list:
$color: blue;
$colors: blue, red, green, yellow;
@for $i from 1 through length($colors) {
@if $color == nth($colors, $i) {
body {
background-color: nth($colors, $i);
}
}
}
In this example, the equal operator is used to check if the value of the $color variable is equal to the value of the current iteration of the loop. If it is, the background color of the body element is set to the value of the current iteration of the loop.
Conclusion
In conclusion, Sass equality operators are special operators that can be used to compare values and make decisions in your stylesheets. Sass provides three types of equality operators: the equal operator (==), the not equal operator (!=), and the matching operator (~). These operators can be used in conjunction with other Sass features such as control directives, loops, and iteration to create more complex stylesheets. It's important to note that all the comparison operators are case-sensitive. Keep in mind that using these operators can make your stylesheet more maintainable and reusable, and they can help you to write more efficient and effective CSS.