# Conditional Statements

Brace supports block-level `{{ if }}` statements and compact in-line conditions.

---

## `if` block

```
{{ if first_name EXISTS }}
<p>Hello {{ first_name }}</p>
{{ end }}
```

---

## `if … else`

```
{{ if first_name EXISTS }}
Hello {{ first_name }} {{ last_name }}
{{ else }}
Name does not exist
{{ end }}
```

---

## `if … elseif … else`

Multiple branches can be chained with `{{ elseif }}`.

```
{{ if name->first && name->last }}
Hello {{ name->first }} {{ name->last }}
{{ elseif name->first }}
Hello {{ name->first }}
{{ elseif name->last }}
Hello Mr {{ name->last }}
{{ else }}
Name does not exist
{{ end }}
```

---

## Conditions inside iterators

Conditions work inside `{{ each }}` blocks and have access to the iteration variables.

```
{{ each names as name }}
    {{ if _ITERATION === "is_first_item" }}
        <span class="first" data-id="{{ _ROW_ID }}">{{ name }}</span>
    {{ elseif _ITERATION === "is_last_item" }}
        <span class="last" data-id="{{ _ROW_ID }}">{{ name }}</span>
    {{ elseif _ITERATION == 2 }}
        <span class="second" data-id="{{ _ROW_ID }}">{{ name }}</span>
    {{ else }}
        <span data-id="{{ _ROW_ID }}">{{ name }}</span>
    {{ end }}
{{ end }}
```

---

## AND / OR conditions

Combine multiple conditions with `&&` (AND) and `||` (OR).

```
{{ if first_name EXISTS && first_name == "John" }}
<p>My first name is {{ first_name }}</p>
{{ else }}
<p>Please enter your first name</p>
{{ end }}
```

```
{{ if role == "admin" || role == "editor" }}
<p>You have write access</p>
{{ end }}
```

---

## In-line conditions

In-line conditions are written inside double braces `{{ }}` and produce a string result directly.

### Syntax

```
{{ condition ? "true output" : "false output" }}
{{ condition ? "true output" }}
```

Placeholders in the output string use `__variable__` syntax (double underscores).

### EXISTS check

```php
<?php

use Brace\Parser;

$brace = new Parser();

echo $brace->parseInputString(
    '{{ name EXISTS ? "Hello __name__" : "No name" }}',
    ['name' => 'Alice'],
    false
)->return();
// Output: Hello Alice
```

### Comparison

```php
echo $brace->parseInputString(
    '{{ first_name !== "test" ? "__first_name__" : "is test" }}',
    ['first_name' => 'John'],
    false
)->return();
// Output: John
```

### Escaping quotes in the output

```php
echo $brace->parseInputString(
    '{{ first_name !== "test" ? "Name is \"__first_name__\"" }}',
    ['first_name' => 'John'],
    false
)->return();
// Output: Name is "John"
```

### AND / OR in in-line conditions

```php
// AND
echo $brace->parseInputString(
    '{{ name EXISTS && age >= 21 ? "Welcome __name__, you are __age__" }}',
    ['name' => 'Simon', 'age' => 21],
    false
)->return();
// Output: Welcome Simon, you are 21

// OR
echo $brace->parseInputString(
    '{{ name === "Dave" || name === "Simon" ? "Hello __name__" : "Stranger" }}',
    ['name' => 'Simon'],
    false
)->return();
// Output: Hello Simon
```

---

## Conditions reference

| Operator  | Description                                              |
|-----------|----------------------------------------------------------|
| `==`      | Equal (loose comparison)                                 |
| `===`     | Identical (strict comparison)                            |
| `!=`      | Not equal (loose comparison)                             |
| `!!`      | Not identical (strict non-equality comparison)           |
| `!==`     | Not identical — alias for `!!`, identical behaviour      |
| `>`       | Greater than                                             |
| `<`       | Less than                                                |
| `>=`      | Greater than or equal to                                 |
| `<=`      | Less than or equal to                                    |
| `EXISTS`  | Variable exists and is non-empty                         |
| `!EXISTS` | Variable does not exist or is empty                      |