Enforce a parameter's declared constraints on an ALREADY type-checked value.
Throws TemplateParameterError naming the parameter — the message is
what the CLI prints and the webapp form shows, so it states the rule, not
the internals. Exported for the clients' early validation (same rule, same
wording, before a render is ever attempted).
Enforce a parameter's declared constraints on an ALREADY type-checked value. Throws TemplateParameterError naming the parameter — the message is what the CLI prints and the webapp form shows, so it states the rule, not the internals. Exported for the clients' early validation (same rule, same wording, before a render is ever attempted).