regexp

9-regular-expressions/11-regexp-groups/01-test-mac/solution.md

@@ -0,0 +1,21 @@
+A two-digit hex number is `pattern:[0-9a-f]{2}` (assuming the flag `pattern:i` is set).
+
+We need that number `NN`, and then `:NN` repeated 5 times (more numbers);
+
+The regexp is: `pattern:[0-9a-f]{2}(:[0-9a-f]{2}){5}`
+
+Now let's show that the match should capture all the text: start at the beginning and end at the end. That's done by wrapping the pattern in `pattern:^...$`.
+
+Finally:
+
+```js run
+let reg = /^[0-9a-fA-F]{2}(:[0-9a-fA-F]{2}){5}$/i;
+
+alert( reg.test('01:32:54:67:89:AB') ); // true
+
+alert( reg.test('0132546789AB') ); // false (no colons)
+
+alert( reg.test('01:32:54:67:89') ); // false (5 numbers, need 6)
+
+alert( reg.test('01:32:54:67:89:ZZ') ) // false (ZZ in the end)
+```

9-regular-expressions/11-regexp-groups/01-test-mac/task.md

@@ -0,0 +1,20 @@
+# Check MAC-address
+
+[MAC-address](https://en.wikipedia.org/wiki/MAC_address) of a network interface consists of 6 two-digit hex numbers separated by a colon.
+
+For instance: `subject:'01:32:54:67:89:AB'`.
+
+Write a regexp that checks whether a string is MAC-address.
+
+Usage:
+```js
+let reg = /your regexp/;
+
+alert( reg.test('01:32:54:67:89:AB') ); // true
+
+alert( reg.test('0132546789AB') ); // false (no colons)
+
+alert( reg.test('01:32:54:67:89') ); // false (5 numbers, must be 6)
+
+alert( reg.test('01:32:54:67:89:ZZ') ) // false (ZZ ad the end)
+```

9-regular-expressions/11-regexp-groups/article.md

@@ -65,7 +65,7 @@ That regexp is not perfect, but mostly works and helps to fix accidental mistype
 
 ## Parentheses contents in the match
 
-Parentheses are numbered from left to right. The search engine remembers the content matched by each of them and allows to get it in the result.
+Parentheses are numbered from left to right. The search engine memorizes the content matched by each of them and allows to get it in the result.
 
 The method `str.match(regexp)`, if `regexp` has no flag `g`, looks for the first match and returns it as an array:
 
@@ -347,4 +347,4 @@ If the parentheses have no name, then their contents is available in the match a
 
 We can also use parentheses contents in the replacement string in `str.replace`: by the number `$n` or the name `$<name>`.
 
-A group may be excluded from remembering by adding `pattern:?:` in its start. That's used when we need to apply a quantifier to the whole group, but don't remember it as a separate item in the results array. We also can't reference such parentheses in the replacement string.
+A group may be excluded from numbering by adding `pattern:?:` in its start. That's used when we need to apply a quantifier to the whole group, but don't want it as a separate item in the results array. We also can't reference such parentheses in the replacement string.