Improve the explanation about backtick templates

examples/index.json

@@ -448,7 +448,7 @@
     "title": "Equality",
     "column": 0,
     "category": "Language concepts",
-    "samples": [ 
+    "samples": [
       {
         "name": "Expression equality",
         "url": "expression-equality",
@@ -1092,15 +1092,13 @@
       {
         "name": "Raw templates",
         "url": "raw-templates",
-        "verifyBuild": false,
-        "verifyOutput": false,
-        "disableVerificationReason": "Includes ballerinax components",
-        "disablePlayground": true,
+        "verifyBuild": true,
+        "verifyOutput": true,
         "isLearnByExample": true
       },
       {
-        "name": "Backtick templates",
-        "url": "backtick-templates",
+        "name": "String templates",
+        "url": "string-templates",
         "verifyBuild": true,
         "verifyOutput": true,
         "isLearnByExample": true
@@ -1111,6 +1109,13 @@
         "verifyBuild": true,
         "verifyOutput": true,
         "isLearnByExample": true
+      },
+      {
+        "name": "Regex templates",
+        "url": "regex-templates",
+        "verifyBuild": true,
+        "verifyOutput": true,
+        "isLearnByExample": true
       }
     ]
   },

examples/raw-templates/raw_templates.md

@@ -11,6 +11,6 @@ An important use case of custom raw templates is SQL parameterized queries.
 ::: out raw_templates.out :::
 
 ## Related links
-- [Backtick templates](https://ballerina.io/learn/by-example/backtick-templates/)
+- [String templates](https://ballerina.io/learn/by-example/string-templates/)
 - [Object type inclusion](https://ballerina.io/learn/by-example/object-type-inclusion/)
 - [Database Access - Simple query](https://ballerina.io/learn/by-example/mysql-query-operation/)

examples/regex-templates/regex_templates.bal

@@ -0,0 +1,17 @@
+import ballerina/io;
+
+public function main() {
+    string:RegExp pat1 = re `a+`;
+    string a0 = "";
+    io:println(pat1.isFullMatch(a0));
+    string a1 = "a";
+    io:println(pat1.isFullMatch(a1));
+    string a2 = "aa";
+    io:println(pat1.isFullMatch(a2));
+
+    string:RegExp pat2 = re `[a-z]+`;
+    string b = "bb";
+    io:println(pat2.isFullMatch(b));
+    string b1 = "bb1";
+    io:println(pat2.isFullMatch(b1));
+}

examples/regex-templates/regex_templates.md

@@ -0,0 +1,5 @@
+# Regex templates
+
+You can use template expressions with `re` tag to create regular expressions. Ballerina regular expressions are based on the ECMAScript 2022 in unicode mode.
+
++ [Regular Expressions](https://ballerina.io/learn/advanced-general-purpose-language-features/#regular-expressions)

examples/regex-templates/regex_templates.metatags

@@ -0,0 +1,2 @@
+description: This BBE demonstrates regex templates in Ballerina.
+keywords: ballerina, ballerina by example, bbe, regex templates, regex

examples/regex-templates/regex_templates.out

@@ -0,0 +1,6 @@
+$ bal run regex_template.bal
+false
+true
+true
+true
+false

examples/string-templates/string_templates.bal

@@ -0,0 +1,21 @@
+import ballerina/io;
+
+public function main() {
+    // Note first \n is treated as is.
+    string s1 = string `line one \n rest of line 1 ${"\n"} second line`;
+    io:println(s1);
+
+    // You can use interpolations to add ` and  $ characters.
+    string s2 = string `Backtick: ${"`"} Dollar: ${"$"}`;
+    io:println(s2);
+
+    // You can nest template expressions.
+    string s3 = string `outer ${string `inner ${5} inner rest`} rest`;
+    io:println(s3);
+
+    // You can use an empty string interpolation to break a template expression
+    // across multiple lines
+    string s4 = string `prefix ${
+                ""}suffix`;
+    io:println(s4);
+}

examples/string-templates/string_templates.md

@@ -0,0 +1,3 @@
+# String templates
+
+A string template is a template expression that can be used to create a string literal. It consists of a `string` tag and a sequence of characters interleaved with interpolations (in the form `${expression}`). Each interpolation must be a subtype of `boolean|int|float|decimal|string`. Every character not a part of the interpolation is interpreted as is to form a sequence of string literals broken at interpolations. This means if you want to add any escape characters you must add them as interpolations (for example `${"\n"}`). Every interpolation is converted to a string using the `toString` method and concatenated with the other string literals to form a single string literal.

examples/string-templates/string_templates.metatags

@@ -0,0 +1,2 @@
+description: This BBE demonstrates string templates in Ballerina.
+keywords: ballerina, ballerina by example, bbe, string templates

examples/string-templates/string_templates.out

@@ -0,0 +1,6 @@
+$ bal run string_templates.bal
+line one \n rest of line 1
+ second line
+Backtick: ` Dollar: $
+outer inner 5 inner rest rest
+prefix suffix