String Functions

Transformation

upper(s)              // Convert to uppercase
lower(s)              // Convert to lowercase
capitalize(s)         // Capitalize first letter
reverse(s)            // Reverse string

Search and Check

contains(s, sub)      // Check if contains substring
startsWith(s, pre)    // Check prefix
endsWith(s, suf)      // Check suffix
indexOf(s, sub)       // Find first occurrence
count(s, sub)         // Count occurrences

Manipulation

trim(s)               // Remove whitespace
replace(s, old, new)  // Replace substring
substring(s, i, j)    // Extract substring
repeat(s, n)          // Repeat string n times

Array Operations

split(s, delim)       // Split into array
join(sep, arr)        // Join array to string

Validation

isEmpty(s)            // Check if empty
isDigit(s)            // Check if all digits
isAlpha(s)            // Check if all letters