9.4.3 CHR Debugging Predicates
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Availability::- use_module(library(chr/chr_runtime)).
Sourcechr_leash(+Spec)
Define the set of CHR ports on which the CHR tracer asks for user intervention (i.e. stops). Spec is either a list of ports as defined in section 9.4.1 or a predefined‘alias’. Defined aliases are: full to stop at all ports, none or off to never stop, and default to stop at the call, exit, fail, wake and apply ports. See also leash/1.