value property
Variables that reference a $(VAR_NAME) are expanded using the previous defined environment variables in the container and any service environment variables.
If a variable cannot be resolved, the reference in the input string will be unchanged. The $(VAR_NAME) syntax can be escaped with a double $$, ie: $$(VAR_NAME). Escaped references will never be expanded, regardless of whether the variable exists or not.
Required.
Implementation
core.String? value;