NAME
Catmandu::Fix::Bind::marc_each - a binder that loops over MARC fields
SYNOPSIS
# Only add the 720 field to the authors when the $e subfield contains a 'promotor'
do marc_each()
if marc_match("720e","promotor")
marc_map("720ab",authors.$append)
end
end
# Delete all the 500 fields
do marc_each()
if marc_match("500",".*")
reject()
end
end
# Loop over all the fields with a variable (see marc_copy, marc_cut and marc_paste for the content)
do marc_each(var:this)
if all_match(this.tag,300)
# The '***' is short for the current tag in a marc_each loop
marc_map(***a,test)
end
end
DESCRIPTION
The marc_each binder will iterate over each individual MARC field and execute the fixes only in context over each individual field.
If a MARC record contains:
500 $aTest
500 $aTest2$eskip
500 $aTest3
then the fix
do marc_each()
marc_map("500",note.$append)
end
will have the same effect as
marc_map("500",note.$append)
because marc_map
by default loops over all repeated MARC fields. But the marc_each
bind has the advantage to process fields in context. E.g. to only map fields where the $e doesn't contain 'skip' you can write:
do marc_each()
unless marc_match("500e",skip)
marc_map("500",note.$append)
end
end
A variable name can be parsed to the marc_each, in which case an automatic marc_copy will be done into the variable name. E.g
do marc_each()
marc_copy(***,this)
...
end
and
do marc_each(var:this)
...
end
is similar