ex_hl7

v0.4.2

ex_hl7 v0.4.2 HL7.Segment.Def

Macros and functions used to define HL7 segments

Link to this section Summary

Functions

build_descriptor(fields)
check_default!(name, seq, type, default)

Check that the default value of a field in a segment is valid

check_field!(name, seq, type, default, length, segment_id, acc)
check_length!(name, seq, type, length)

Check that the length of a field in a segment is valid

check_name_seq!(name, seq, segment_id, fields)
check_type!(name, seq, type)

Check that the type of a field in a segment is valid

descriptor_map(tuple, fun)
field(name, options)

Macro that injects the code used to represent a field within an HL7 segment block. Each field definition looks like the following one

segment(segment_id, list)

Macro that generates the code that allows a module to be used as an HL7 segment. A segment definition looks like the following block

Link to this section Functions

Link to this function build_descriptor(fields) 
build_descriptor([{name :: atom, seq :: pos_integer, type :: atom, length :: pos_integer}]) :: tuple
Link to this function check_default!(name, seq, type, default)

Check that the default value of a field in a segment is valid

Link to this function check_field!(name, seq, type, default, length, segment_id, acc)
Link to this function check_length!(name, seq, type, length)

Check that the length of a field in a segment is valid

Link to this function check_name_seq!(name, seq, segment_id, fields)
Link to this function check_type!(name, seq, type)

Check that the type of a field in a segment is valid

Link to this function descriptor_map(tuple, fun)
Link to this macro field(name, options) (macro)

Macro that injects the code used to represent a field within an HL7 segment block. Each field definition looks like the following one:

field :diagnosis_type, seq: 6, type: :binary, length: 2

A field has a name that has to be an atom, a seq number (1-based) with the field’s position in the segment, a type and a length. The default type is :string and the default length is nil. The supported types are:

  • :string
  • :integer
  • :float
  • :date: a field containing a date as a {year, month, day} that is serialized using the YYYYMMDD format.
  • :datetime: a field containing a date/time tuple (i.e. {{year, month, day}, {hour, min, sec}}) that is serialized using the *YYYYMMDD[hhmm[ss]] format.
  • an atom corresponding to a composite field’s module name. The module must have been built using the macros from the HL7.Composite.Def module or following the behaviour of an HL7.Composite. There are some sample composite field modules already defined in the HL7.Composite module.
Link to this macro segment(segment_id, list) (macro)

Macro that generates the code that allows a module to be used as an HL7 segment. A segment definition looks like the following block:

alias HL7.Composite.CE

segment "DG1" do
  field :set_id,         seq:  1, type: :integer,  length:  4
  field :diagnosis,      seq:  3, type: CE,        length: 64
  field :diagnosis_type, seq:  6, type: :binary,   length:  2
end

A segment has a name or segment ID, which is a binary that will be used to identify the segment when parsing an HL7 message or when converting the segment into its wire format.

Note: when defining a segment, the fields with correlative sequence (seq) numbers need not be in order, but it is recommended that you do so.