v1.16.5/internal/command/testdata/dynamic-module-sources/const-var-source-with-validation/main.tf

variable "module_name" {
  type  = string
  const = true
  validation {
    condition     = var.module_name == "example"
    error_message = "The module_name variable must be set to \"example\""
  }
}

module "example" {
  source = "./modules/${var.module_name}"
}