lower

lower(str) returns a copy of str with all letters converted to lowercase.

Signature

lower(str string) string

Example

Normalize a branch name to lowercase before using it as a Docker image tag. Branch names may contain uppercase letters from conventions like feature/UserAuth, which are not valid in image tag format:

variable "branch" {
  description = "Git branch name"
  type        = string
}

computed "image_tag" {
  description = "Docker-safe image tag from the branch name"
  expression  = lower(replace(var.branch, "/", "-"))
}

task "build" {
  description = "Build a branch-tagged Docker image"
  commands    = ["docker build -t myapp:${computed.image_tag} ."]
}

feature/UserAuth becomes feature-userauth.

Notes

lower converts all Unicode letters, not just ASCII.
Pair lower with replace or regexreplace to sanitize strings for use in identifiers, tags, or filenames.

Overview

String

Number

Collection

Encoding

Crypto

Filesystem

Datetime

Regex

UUID

Conversion

Environment

Runtime

Signature

Example

Notes

​Signature

​Example

​Notes

Signature

Example

Notes