Combine string containers

[maddenp-cu]

Synopsis

To avoid confusion about where to define string constants, combine the EC and STR string containers. For now, the FORMAT container remains, since its class offers some helper methods specific to data formats.

Type

• Code maintenance (refactoring, etc. without behavior change)

Impact

• This is a non-breaking change (existing functionality continues to work as expected)

Checklist

• I have added myself and any co-authors to the PR's Assignees list.
• I have reviewed the documentation and have made any updates necessitated by this change.
• Where helpful, I have written comments in this PR's Files changed view to assist reviewers.