Concept exercise: Template string and Ternary (#1428)

Author: pertrai1

concepts/conditionals-ternary/.meta/config.json

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+{
+  "blurb": "The conditional ternary operator is used to write a condensed expression that returns one of two alternate values based on some condition.",
+  "authors": ["pertrai1"],
+  "contributors": []
+}

concepts/conditionals-ternary/about.md

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+# About
+
+The conditional ternary operator is used to write a condensed expression that returns one of two alternate values based on some condition.
+It is often referred to as the "ternary operator".
+The name stems from the fact that the operator has three operands: `predicate ? consequent-expression : alternative-expression`
+It can be used as a replacement for short if-else statements.
+
+Similar to `if` statements, JavaScript will perform implicit type conversion to evaluate the condition.
+If the condition is truthy, the operand on the left-hand side of the colon will be returned.
+Otherwise the result of the ternary expression is the operand on the right-hand side of the colon.
+
+```javascript
+const year = 2020;
+
+year > 2000 ? 'in the past years' : 'a long time ago';
+// => 'in the past years'
+```

concepts/conditionals-ternary/introduction.md

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+# Introduction
+
+The conditional ternary operator is used to write a condensed expression that returns one of two alternate values based on some condition.
+It is often referred to as the "ternary operator".
+The name stems from the fact that the operator has three operands: `predicate ? consequent-expression : alternative-expression`
+It can be used as a replacement for short if-else statements.
+
+Similar to `if` statements, JavaScript will perform implicit type conversion to evaluate the condition.
+If the condition is truthy, the operand on the left-hand side of the colon will be returned.
+Otherwise the result of the ternary expression is the operand on the right-hand side of the colon.
+
+```javascript
+const year = 2020;
+
+year > 2000 ? 'in the past years' : 'a long time ago';
+// => 'in the past years'
+```

concepts/conditionals-ternary/links.json

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+[
+  {
+    "url": "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array#Instance_methods",
+    "description": "MDN: Conditional (ternary) operator"
+  },
+  {
+    "url": "https://javascript.info/ifelse",
+    "description": "javascript.info: Conditional branching"
+  }
+]

concepts/string-formatting/.meta/config.json

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+{
+  "blurb": "You can create template strings in JavaScript by wrapping text in backticks. They not only allow the text to include new lines and other special characters, you can also embed variables and other expressions.",
+  "authors": ["pertrai1"],
+  "contributors": []
+}

concepts/string-formatting/about.md

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+# Introduction
+
+In JavaScript, _template strings_ allows for embedding expressions in strings, also referred to as string interpolation.
+This functionality extends the functionality of the built in [`String`][string-reference] global object.
+
+You can create template strings in JavaScript by wrapping text in backticks.
+They not only allow the text to include new lines and other special characters, you can also embed variables and other expressions.
+
+```javascript
+const num1 = 1;
+const num2 = 2;
+
+`Adding ${num1} and ${num2} gives ${num1 + num2}.`;
+// => Adding 1 and 2 gives 3.
+```
+
+In the example above, backticks - (<code>\`\`</code>) - are used to represent a template string. The`${...}` is the placeholder that is used for substitution.
+Any non-string types are _implicitly_ converted to strings.
+This topic is covered in the [type conversion][type-conversion-concept] concept.
+All types of expressions can be used with template strings.
+
+```javascript
+const track = 'JavaScript';
+
+`This track on exercism.io is ${track.toUpperCase()}.`;
+// => This track on exercism.io is JAVASCRIPT.
+```
+
+When you are needing to have strings formatted on multiple lines:
+
+```javascript
+`This is example of using template
+strings to accomplish multiple
+lines`;
+```
+
+With the substitution capabilities that are available, you can also introduce logic into the process to determine what the output string should be.
+One way to handle the logic could be using the [ternary operator][ternary-operator].
+This gives the same conditional `if/else` functionality in a slightly different format.
+
+To implement logic into template string syntax:
+
+```javascript
+const grade = 95;
+
+`You have ${grade > 90 ? 'passed' : 'failed'} the exam.`;
+// => You have passed the exam.
+```
+
+[string-reference]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String
+[type-conversion-concept]: /tracks/javascript/concepts/type-conversion
+[ternary-operator]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional_Operator