Explicit quantifiers are positioned following the pattern they apply to, just like regular quantifiers.
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Below are some sample patterns and inputs they would match. (period or dot) metacharacter is one of the simplest and most used. This can be useful for specifying that certain patterns can contain any combination of characters, but must fall within certain length ranges by using quantifiers.
The constructs within regular expressions that have special meaning are referred to as metacharacters. Also, we have seen that expressions will match any instance of the pattern they describe within a larger string, but what if you only want to match the pattern exactly?
For example, x would match exactly five x characters (xxxxx).
When only one number is specified, it is used as the upper bound unless it is followed by a comma, such as x, which would match any number of x characters greater than 4.
In addition to the non-explicit quantifiers (generally just referred to as quantifiers, but I'm distinguishing them from this next group), there are also quantifiers.
Where quantifiers are fairly vague in terms of how many occurrences there may be of a pattern, explicit quantifiers allow an exact number, range, or set of numbers to be specified.
Now you've gone beyond what literal strings can do (within reason)—it's time to learn some more about regular expressions.
Below is a sample literal expression and some inputs it would match.
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