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HELP TWIDDLYBRA Steven Hardy Mar 1982 Updated: Adrian Howard Mar 1992 Twiddly brackets, "{" and "}", tell the POP-11 system to build a vector of the enclosed items. For example, below is a vector of words and numbers: {2 cats 3 dogs 5 birds} Vectors can be nested. Percent symbols (%) and up-arrows (^ and ^^) can be used within a vector expression to cause part of the expression to be evaluated rather than quoted, e.g. vars n1=3, n2=5, n3=7; { ^n1 cats ^n2 dogs ^n3 birds }=> ** {3 cats 5 dogs 7 birds} Twiddly brackets may be preceded by -cons_with- to create other structures than vectors (see HELP *CONS_WITH.) See TEACH *BRACKETS for a tutorial introduction to the use of brackets in POP-11, and TEACH *ARROW for the use of up-arrows. Also see: * PERCENT --- Uses of the % symbol in POP-11 * INITV --- Construction of vectors * CONSVECTOR * SUBSCRV --- Accessing and updating vector elements * SQUAREBRA --- Constructing lists using square brackets * ROUNDBRA --- The use of round brackets in POP-11 * #_< --- Compilation brackets * #| --- Stack counting brackets --- C.all/help/twiddlybra --- Copyright University of Sussex 1992. All rights reserved. ----------