A.5 Operator Precedence

The operators at the top of the table bind more tightly than those lower down.

Class	Operators	Description	Associativity
Application	f(0)	function application
	[[ <- ]]	renaming
Arithmetic	-	unary minus
	*, /, %	multiplication	left
	+, -	addition	left
Sequence	^	catenation
	#	length
Comparisons	<, >, <=, >=	ordering	none
	==, !=	equality	none
Boolean	not	negation
	and	conjunction
	or	disjunction
Sequential	->	prefix
	&	guard
	;	sequence
Choice	[>	untimed timeout
	/\	interrupt
	[]	external choice
	[+ +]	delayed choice
	|~|	internal choice
	[| |>	exception
Parallel	[| |], [ || ], [ <-> ]	parallel	none
	|||	interleave
Other	if then else	conditional
	let within	local definitions
	\ @	lambda term

The replicated versions of the process operators have the lowest predence of all. The @@ pattern operator has a precedence just below that of function application.

Note that this table represents a simplification of the acual parser rules. For example, the parser will intrepret ‘#s+1’ as ‘(#s)+1’, which does not strictly agree with the table, since the parser is making (limited) use of type information.

This document was generated by Phil Armstrong on May 17, 2012 using texi2html 1.82.