You need to double the backslashes used to escape the regular expression special characters. However, as @Bohemian points out, most of those backslashes aren’t needed. Unfortunately, his answer suffers from the same problem as yours. What you actually want is: The backslash is being interpreted by the code that reads the string, rather than passed …
You can do it with either of these: sed ‘s/.*six.*/fault/’ file # check all lines sed ‘/six/s/.*/fault/’ file # matched lines -> then remove It gets the full line containing six and replaces it with fault. Example: $ cat file six asdf one two six one isix boo $ sed ‘s/.*six.*/fault/’ file fault asdf fault …
Javascript doesn’t support interpolation like Ruby — you have to use the RegExp constructor: var aString = “foobar”; var pattern = “bar”; var matches = aString.match(new RegExp(pattern));
Pass a string to RegExp or create a regex using the // syntax Call regex.test(string), not string.test(regex) So jQuery(function () { $(“.mail”).keyup(function () { var VAL = this.value; var email = new RegExp(‘^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$’); if (email.test(VAL)) { alert(‘Great, you entered an E-Mail-address’); } }); });
This should do the trick: df[- grep(“REVERSE”, df$Name),] Or a safer version would be: df[!grepl(“REVERSE”, df$Name),]
function isEmpty(obj) { return Object.keys(obj).length === 0; }
You can Use $options => i for case insensitive search. Giving some possible examples required for string match. Exact case insensitive string db.collection.find({name:{‘$regex’ : ‘^string$’, ‘$options’ : ‘i’}}) Contains string db.collection.find({name:{‘$regex’ : ‘string’, ‘$options’ : ‘i’}}) Start with string db.collection.find({name:{‘$regex’ : ‘^string’, ‘$options’ : ‘i’}}) End with string db.collection.find({name:{‘$regex’ : ‘string$’, ‘$options’ : ‘i’}}) Doesn’t …
To count all occurrences, use -o. Try this: echo afoobarfoobar | grep -o foo | wc -l And man grep of course (: Update Some suggest to use just grep -co foo instead of grep -o foo | wc -l. Don’t. This shortcut won’t work in all cases. Man page says: -c print a count …
You need to double the backslashes used to escape the regular expression special characters. However, as @Bohemian points out, most of those backslashes aren’t needed. Unfortunately, his answer suffers from the same problem as yours. What you actually want is: The backslash is being interpreted by the code that reads the string, rather than passed …
Although the match function doesn’t accept string literals as regex patterns, you can use the constructor of the RegExp object and pass that to the String.match function: var re = new RegExp(yyy, ‘g’); xxx.match(re); Any flags you need (such as /g) can go into the second parameter.