condition assign to const variable - reactjs

Question

I am doing a regex where I am checking for the condition with certain names.
const nameMatch = () => {
return ( !this.state.name.match("^Jen.*") || !this.state.name.endsWith("ez") );
}
In this, I get the values of nameMatch as () => { return ( !this.state.name.match("^Jen.*") || this.state.name.endsWith("ez") ); } rather than true or not
I am doing if(nameMatch) {...}
but rather I would need the ones that match.
What am I doing wrong?

Answer 1

A breakdown of the regex "^Jen.*":
^ asserts the position the start of a line, where lines are delimited by \n.
Jen is a case sensitive match for the characters "Jen".
.* matches any character except for line terminators (\n) between zero and unlimited times.
Therefore as I understand your question, you're asking how to find and return every name which does not start with "Jen" or end with "ez".
If this.state.name is an Array of names, then you can return all of the names that do not start with "Jen" or end with "ez" using the following example:
var names = ['menez', 'asJenas', 'benez', 'destruction', 'present', 'Jenosus', 'ezJen'];
const nameMatch = names.filter((word) => {
return !(word.startsWith("Jen") || word.endsWith("ez"));
});
console.log(nameMatch);
// expected output: Array ["asJenas", "destruction", "present", "ezJen"]
If this.state.name is a String containing multiple names with new line (\n) delimiters in it, then you can first extract an array of names from the string and then use the above code, for example:
var names = "menez\nasJenas\nbenez\ndestruction\npresent\nJenosus\nezJen"
const namesArray = names.split("\n");
const nameMatch = namesArray.filter((word) => {
return !(word.startsWith("Jen") || word.endsWith("ez"));
});
console.log(nameMatch);
// expected output: Array ["asJenas", "destruction", "present", "ezJen"]
If this.state.name is a String containing a single name, then you can use the following function, which will return true if the name does not start with "Jen" or end with "ez":
const nameMatch = (name) => {
return !(name.startsWith("Jen") || name.endsWith("ez"));
};
You can use it like so:
const nameMatch = (name) => {
return !(name.startsWith("Jen") || name.endsWith("ez"));
};
var names = "Ben";
if (nameMatch(names)) {
console.log("This name matched");
}
// expected output: "This name matched"
Please keep in mind that where I have used names, you will need to swap it to this.state.name.

Answer 2

You are assigning a function to the const nameMatch.
These types of functions are called fat arrow functions.
If you wanted to get the value in the nameMatch variable, you can try:
const nameMatch = (!this.state.name.match("^Jen.*") || !this.state.name.endsWith("ez"))
A simpler way of expressing the logic is:
const nameMatch = !(this.state.name.match("^Jen.*") && this.state.name.endsWith("ez"))

Answer 3

nameMatch is a function, so you need execute it to get the result, just call nameMatch() instead nameMatch