The source code for Tcl is managed by fossil. Tcl developers coordinate all changes to the Tcl source code at
Release Tcl 9.1a0 arises from the check-in with tag core-9-1-a0.
Highlighted differences between Tcl 9.1 and Tcl 9.0 are summarized below, with focus on changes important to programmers using the Tcl library and writing Tcl scripts.
New public C API
- Tcl_IsEmpty checks if the string representation of a value would be the empty string
- Tcl_GetEncodingNameForUser returns name of encoding from user settings
- Tcl_AttemptCreateHashEntry - version of Tcl_CreateHashEntry that returns NULL instead of panic'ing on memory allocation errors
Performance
- Memory efficient internal representations for list operations on large lists.