I have this following problem. i try to split a string up depending on a regex.
I want to to split it by {{ name }}, {{ age }} and so on.
The expected output should look like this:
["hy my name is: ", "{{ name }}", " and i am ", "{{ age }}", " old"]
My current attempt was this here:
let str = "hy my name is: {{ name }} and i am {{ age }} old";
let vars = str.split(/({{)(.*)(}})/);
console.log(vars);Whats the correct regex for this task?
You need to
split if it is captured: "If separator is a regular expression that contains capturing parentheses (), matched results are included in the array."., .*?, instead of the greedy .*. Otherwise, the {{.*}} will match {{, then any 0 or more chars other than line break chars as many as possible, and then }}, so all {{...}} substrings in between {{ and }} will be put into one match.JS fixed demo:
let str = "hy my name is: {{ name }} and i am {{ age }} old";
let vars = str.split(/({{.*?}})/);
console.log(vars);
// => [ "hy my name is: ", "{{ name }}", " and i am ", "{{ age }}", " old"]Note that { and } are only special if there is a number inside, like {6}. In {{.*?}}, the curly braces cannot be parsed as limiting quantifiers since there is no number, hence, you may escape { chars in order to prevent any ambiguity.
Also, in case you have a match at the start of the string, you will have an empty element in the resulting array, then you need to remove the empty elements:
str.split(/({{.*?}})/).filter(Boolean)
Instead of split, you may use this regex with match:
/{{.*?}}|.+?(?={{|$)/g
Code:
let str = "hy my name is: {{ name }} and i am {{ age }} old";
let vars = str.match(/{{.*?}}|.+?(?={{|$)/g);
console.log(vars);RegEx Details:
{{.*?}}: Match a string within {{...}}|: OR.+?: Match 1+ of any character that satisfies next lookahead condition(?={{|$): Positive lookahead condition that makes sure that we have wither {{ or end of line at next position