Main Index

An italic page number such as 123 indicates a definition. A light page number such as 456 indicates a brief mention. Page numbers followed by the letter t refer to tables. Only variables that must always appear with a leading dollar sign are indexed with a leading dollar sign. Other variables are indexed without a leading dollar sign.

Symbols

,(comma) operator 510

; control operator 149, 300, 512

;; control operator 454, 512

: (null) builtin 486, 498

:- substitutes default values for a variable 485

:? sends to standard error an error message for a variable 486

:= assigns default values for a variable 485

! (NOT) Boolean operator 511, 678

! event reference 341

!! reexecutes the previous event 341

? in extended regular expressions

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