Operators

Operators perform specific operations on values in Expression Language. They enable:

• Calculations
• Comparisons
• Logical decisions
• String manipulation
• Data access

This reference covers every available operator with syntax examples and common usage patterns.

Arithmetic Operators

Mathematical operations for calculations and numeric transformations.

Operator	Name	Syntax	Example	Result	Usage
+	Addition	a + b	5 + 3	8	Add numbers, calculate totals
-	Subtraction	a - b	10 - 4	6	Subtract values, find differences
*	Multiplication	a * b	6 * 7	42	Multiply numbers, calculate percentages
/	Division	a / b	15 / 3	5	Divide numbers, find averages
%	Modulus	a % b	17 % 5	2	Find remainder, check even/odd
**	Exponentiation	a ** b	2 ** 3	8	Calculate powers, exponential growth

Practical examples:

# Calculate total price including tax rate
[[price + (price * tax_rate)]]

# Apply percentage discount to original price  
[[original_price - (original_price * discount_percentage / 100)]]

# Alternate CSS classes for table rows
[[index % 2 == 0 ? 'even-row' : 'odd-row']]

# Calculate compound interest over time
[[principal * (1 + rate) ** years]]

Comparison Operators

Compare values and return boolean results for conditional logic.

Operator	Name	Syntax	Example	Result	Usage
==	Equal	a == b	5 == '5'	true	Loose equality, type conversion
===	Identical	a === b	5 === '5'	false	Strict equality, no type conversion
!=	Not Equal	a != b	5 != 3	true	Loose inequality
!==	Not Identical	a !== b	5 !== '5'	true	Strict inequality
<	Less Than	a < b	3 < 5	true	Numeric and alphabetical comparison
>	Greater Than	a > b	10 > 5	true	Numeric and alphabetical comparison
<=	Less Than or Equal	a <= b	5 <= 5	true	Inclusive comparison
>=	Greater Than or Equal	a >= b	10 >= 8	true	Inclusive comparison

Practical examples:

# Display different text based on post status
[[post_status == 'publish' ? 'Live' : 'Draft']]

# Check if price falls within acceptable range
[[price >= min_price and price <= max_price]]

# Set user category based on age threshold
[[user_age >= 18 ? 'Adult' : 'Minor']]

# Show availability based on inventory count
[[inventory > 0 ? 'In Stock' : 'Out of Stock']]

Logical Operators

Combine and manipulate boolean values for complex conditional logic.

Operator	Name	Syntax	Example	Result	Usage
and / &&	Logical AND	a and b	true and false	false	Both conditions must be true
or / ||	Logical OR	a or b	true or false	true	At least one condition must be true
not / !	Logical NOT	not a	not true	false	Negates/reverses boolean value

Truth tables and examples:

# Require all conditions to be met
[[is_logged_in and has_permission and is_active]]

# Allow access if user has any qualifying role  
[[is_admin or is_editor or is_moderator]]

# Check for opposite condition
[[not is_guest_user]]

# Complex permission checking with grouped conditions
[[is_logged_in and (is_admin or is_editor) and not is_suspended]]

String Operators

Manipulate and combine text values.

Operator	Name	Syntax	Example	Result	Usage
~	Concatenation	a ~ b	'Hello' ~ ' World'	'Hello World'	Join strings together

Practical examples:

# Combine first and last name with space
[[first_name ~ ' ' ~ last_name]]

# Build dynamic URL from base and page number
[[base_url ~ '/page/' ~ page_number]]

# Format price display with currency symbol
[['Price: $' ~ price ~ ' (' ~ currency ~ ')']]

# Add draft indicator to unpublished posts
[[post_title ~ (post_status != 'publish' ? ' [DRAFT]' : '')]]

About Concatenation Operator

Even if you concatenate non-strings, the output will be a string. For example 1 ~ 2 evaluates to "12" not 12. This means you also cannot concatenate dynamic data, for eg. wp. ~ .post ~ .title will render as wp.post.title not Hello World!

Array Operators

Test array membership and create ranges.

Operator	Name	Syntax	Example	Result	Usage
in	Contains	value in array	'red' in ['red', 'blue']	true	Check if value exists in array
not in	Does Not Contain	value not in array	'green' not in ['red', 'blue']	true	Check if value missing from array
..	Range	start..end	1..5	[1,2,3,4,5]	Generate numeric sequences

Practical examples:

# Check if post has any acceptable status
[[post_status in ['publish', 'future', 'private']]]

# Exclude posts from banned or inactive users
[[user_role not in ['banned', 'suspended', 'inactive']]]

# Validate current page within total page count
[[current_page in 1..total_pages]]

# Grant access based on user role membership
[[user_role in ['admin', 'editor'] ? 'Edit Access' : 'Read Only']]

Access Operators

Navigate object properties and array elements.

Operator	Name	Syntax	Example	Result	Usage
.	Property Access	object.property	user.display_name	Property value	Access object properties
[]	Array Access	array[index]	posts[0]	Array element	Access array elements by index

Practical examples:

# Access nested user information from post
[[wp.post.post_author.display_name]]

# Get name from first category in array
[[categories[0].name]]

# Access featured image URL property
[[featured_image.file_url]]

# Get title from first post in query results
[[wp.posts_query.posts[0].post_title]]

Conditional Operators

Make decisions and provide fallback values.

Operator	Name	Syntax	Example	Result	Usage
? :	Ternary	condition ? true_val : false_val	age >= 18 ? 'Adult' : 'Minor'	Conditional result	If/then/else logic
??	Null Coalescing	value ?? fallback	custom_title ?? post_title	First non-null value	Provide fallback values

Practical examples:

# Show personalized greeting based on login status
[[is_logged_in ? 'Welcome back!' : 'Please log in']]

# Handle multiple post states with nested conditions
[[post_status == 'publish' ? 'Published' : (post_status == 'draft' ? 'Draft' : 'Other')]]

# Use first available content source
[[custom_excerpt ?? post_excerpt ?? limit_words(post_content, 30)]]

# Display price or unavailable message with formatting
[[(inventory > 0 and price > 0) ? ('$' ~ price ~ ' - Available') : 'Out of Stock']]

Specialized Operators

Advanced operators for specific use cases.

Operator	Name	Syntax	Example	Result	Usage
matches	Regex Match	string matches pattern	email matches '/^.+@.+$/'	true/false	Pattern matching validation
&	Bitwise AND	a & b	5 & 3	1	Binary operations (advanced)
|	Bitwise OR	a | b	5 | 3	7	Binary operations (advanced)
->	Arrow Function	(param) -> expression	(item) -> item.active	Function	Callback functions for arrays

Practical examples:

# Validate email format using regex pattern
[[email matches '/^[^@]+@[^@]+\.[^@]+$/' ? 'Valid' : 'Invalid']]

# Detect gallery shortcode in post content
[[post_content matches '/\\[gallery.*?\\]/' ? 'Has Gallery' : 'No Gallery']]

# Filter array to published posts only
[[filter(posts, (post) -> post.post_status == 'publish')]]

# Check permission flags using bitwise operation
[[user_permissions & admin_flag]]

Operator Precedence

Operations are evaluated in specific order. Higher precedence = evaluated first.

Precedence	Operators	Description
500	+ - (unary)	Positive/negative signs
200	**	Exponentiation
60	* / %	Multiplication, division, modulus
40	~	String concatenation
30	+ -	Addition, subtraction
25	..	Range
20	< > <= >= == === != !== in not in matches	Comparisons
15	and &&	Logical AND
10	or ||	Logical OR
5	->	Arrow functions
0	? :	Ternary conditional

Precedence examples:

# Multiplication happens before addition
[[2 + 3 * 4]]  # Result: 14 (not 20)

# Override precedence with parentheses
[[(2 + 3) * 4]]  # Result: 20

# Logical operations follow precedence rules
[[price > 100 and quantity > 0 or is_sale]]  
# Evaluates as: (price > 100 and quantity > 0) or is_sale

# Use parentheses for clarity in complex expressions
[[(price > 100 and quantity > 0) or is_sale]]

Common Patterns

Range Checking

[[price >= 50 and price <= 100]]
[[user_age >= 13 and user_age <= 17]]

Status Badges

[[post_status == 'publish' ? 'Live' : 'Draft']]
[[inventory > 0 ? 'Available' : 'Sold Out']]

Safe Operations

# Prevent division by zero
[[total > 0 ? amount / total : 0]]

# Safe string operations
[[title ?? 'Untitled']]

Multiple Conditions

[[is_logged_in and has_permission and not is_banned]]
[[is_sale or (price < 20) or (is_member and price < 50)]]

Common Mistakes

Mistake	Wrong	Correct	Why
Assignment vs Comparison	status = 'active'	status == 'active'	Use == for comparison
String Addition	'Hello' + 'World'	'Hello' ~ 'World'	Use ~ for string concatenation
Precedence	5 + 3 * 2	(5 + 3) * 2	Use parentheses for clarity
Incomplete Ternary	condition ? 'yes'	condition ? 'yes' : 'no'	Ternary needs both values
Type Confusion	'5' === 5	'5' == 5	Use == for loose comparison

Expression Language Functions

For data transformation capabilities, see: Built-in Functions → - 100+ functions for processing and transforming data

Expression Syntax

For complete syntax rules and structure, see: Expression Syntax → - Language structure, data access, and formatting rules

Operators are the building blocks of Expression Language logic. Master these patterns to create sophisticated conditional logic, calculations, and data transformations throughout your Builderius templates.