Chapter 11: Functions¶

pyvider.cty provides a rich, built-in standard library of functions for manipulating cty values. These functions are type-safe and operate on CtyValue instances, returning new CtyValue instances.

Calling Functions¶

You can call a cty function by importing it from the pyvider.cty.functions module.

from pyvider.cty import CtyNumber
from pyvider.cty.functions import add, abs_fn

num1 = CtyNumber().validate(10)
num2 = CtyNumber().validate(-20)

# Add two numbers
sum_val = add(num1, num2)
assert sum_val.raw_value == -10

# Get the absolute value
abs_val = abs_fn(num2)
assert abs_val.raw_value == 20

Overview of Available Functions¶

The standard library is extensive. Below is a categorized overview with function descriptions.

Numeric Functions¶

Function	Description
`add`	Add two numbers
`subtract`	Subtract second number from first
`multiply`	Multiply two numbers
`divide`	Divide first number by second
`modulo`	Calculate modulo (remainder) of division
`pow_fn`	Raise first number to power of second
`abs_fn`	Return absolute value of a number
`ceil_fn`	Round number up to nearest integer
`floor_fn`	Round number down to nearest integer
`int_fn`	Convert number to integer (truncate decimals)
`log_fn`	Calculate natural logarithm
`signum_fn`	Return sign of number (-1, 0, or 1)
`parseint_fn`	Parse string as integer in given base
`negate`	Negate a number (multiply by -1)
`max_fn`	Return maximum of two numbers
`min_fn`	Return minimum of two numbers

String Functions¶

Function	Description
`upper`	Convert string to uppercase
`lower`	Convert string to lowercase
`title`	Convert string to title case
`strrev`	Reverse a string
`chomp`	Remove trailing newline from string
`indent`	Add indentation to each line
`trim`	Remove leading and trailing whitespace
`trimspace`	Remove all leading/trailing whitespace
`trimprefix`	Remove prefix from string if present
`trimsuffix`	Remove suffix from string if present
`join`	Join list of strings with separator
`split`	Split string by separator into list
`replace`	Replace occurrences of substring
`substr`	Extract substring by position and length
`regex`	Match string against regular expression
`regexall`	Find all regex matches in string
`regexreplace`	Replace regex matches in string

Collection Functions¶

Function	Description
`length`	Return number of elements in collection
`slice`	Extract subset of list elements
`concat`	Concatenate multiple lists
`contains`	Check if collection contains value
`reverse`	Reverse order of list elements
`distinct`	Remove duplicate elements from list
`flatten`	Flatten nested lists into single list
`sort`	Sort list elements
`keys`	Get keys from map or object
`values`	Get values from map or object
`lookup`	Look up value in map by key with default
`merge`	Merge multiple maps into one
`zipmap`	Create map from list of keys and list of values
`element`	Get element at specific index (with wraparound)
`chunklist`	Split list into chunks of specified size
`setproduct`	Calculate Cartesian product of sets
`compact`	Remove null/empty values from list
`coalescelist`	Return first non-empty list
`index`	Find index of value in list
`hasindex`	Check if collection has element at index

Comparison Functions¶

Function	Description
`equal`	Test if two values are equal
`not_equal`	Test if two values are not equal
`greater_than`	Test if first > second
`less_than`	Test if first < second
`greater_than_or_equal_to`	Test if first >= second
`less_than_or_equal_to`	Test if first <= second

Type Conversion Functions¶

Function	Description
`to_string`	Convert value to string
`to_number`	Convert value to number
`to_bool`	Convert value to boolean

Encoding Functions¶

Function	Description
`jsonencode`	Encode value as JSON string
`jsondecode`	Decode JSON string to value
`csvdecode`	Decode CSV string to list of maps

Date/Time Functions¶

Function	Description
`formatdate`	Format timestamp string using format spec
`timeadd`	Add duration to timestamp

Bytes Functions¶

Function	Description
`byteslen`	Return length of bytes value
`bytesslice`	Extract slice of bytes

Structural Functions¶

Function	Description
`coalesce`	Return first non-null value from arguments

For complete API documentation with detailed signatures and examples, see the Functions API Reference.