[expr] "raise to power" operator, similar to [pow] function Returns an integer value if both arguments are integers, and [double]-precision floating-point otherwise. The left operand may be any integer from Tcl's unlimited integer range. The right operand is limited to a max integer value of 268435455 (0xfffffff) (28 bits). (Unless the left operand is -1, 0, or 1, so that the answer is trivial). Expect to wait a long while for [[expr 2**0xfffffff]] to return. ---- **Precedence** During early 2009, a thread broke out in the comp.lang.tcl usenet group discussing the observation that Tcl's calculation for ====== puts [expr {-2**2}] ====== surprised someone who was expecting that to mean ====== puts [expr {-(2**2)} ====== while Tcl's operator precedence rules cause it to mean ====== puts [expr {(-2)**2} ====== ---- !!!!!! %| [Category Operator] | [Category Command] | [Category Mathematics] |% !!!!!!