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#!/usr/bin/guile \
-e main -s
!#
(add-to-load-path (dirname (current-filename)))
(use-modules (srfi srfi-1)
(srfi srfi-8)
(srfi srfi-9)
(srfi srfi-26)
(ice-9 rdelim)
(ice-9 peg)
(patterns))
;; var is the field to test
;; symb is the expected value
(define-syntax-rule (ensure-symbol var symb)
(unless (eqv? var symb)
(throw 'symbol-not-equal "Expected ~s, got ~s~%" symb var)))
(define (read-csv port)
"Read from port into a peg:tree."
(let* ((rawstr (read-delimited "" port))
(match (match-pattern file rawstr))
(tree (keyword-flatten '(line)
(peg:tree match))))
tree))
;;; TODO sometimes part is a symbol instead of a list,
;;; somehow an earlier part got consed on? or something?
(define (get-part-data part)
"Get data from field-part cells"
(if (symbol? part)
#f
(begin
(ensure-symbol (car part) 'field-part)
(cadr part))))
(define (flatten-1 lst)
"If list is of length one return the first element,
otherwise return the full list"
(if (= 1 (length lst))
(car lst)
lst))
;; ('line ('field ('field-part data) ...) ...)
;; -> ({(data ...) | data} ...)
(define (clean-peg-tree tree)
"Clean up input from read-csv, returns a more bare bones tree"
(map (lambda (line) ; for every line
(ensure-symbol (car line) 'line)
(map (lambda (field) ; for every field in line
(and (not (symbol? field)) ; if a symbol no data is present
;; else extract the data
(begin (ensure-symbol (car field) 'field)
(flatten-1 (map get-part-data (cdr field))))))
(cdr line)))
tree))
;;; Takes (car (clean-peg-tree csv))
;;; name is a string
;;; returns a record-type, a constructor, a predicate procedure,
;;; and an association list of getters
(define (create-csv-record name field-strings)
"Creates datatypes from csv records"
(let ((full-name (string-append "csv:" name))
(fields (map string->symbol field-strings)))
(let* ((record-type (make-record-type full-name fields))
(make-record (record-constructor record-type fields))
(predicate (record-predicate record-type))
(accessors (map cons fields
(map (cut record-accessor record-type <>)
fields))))
(values record-type make-record predicate accessors))))
;;; filename -> [book]
(define (load-data csv-file-name)
(let* ((csv (call-with-input-file csv-file-name read-csv))
(tree (clean-peg-tree csv))
(fields (car tree))
(data (cdr tree)))
(receive (book make-book book? book-getters)
(create-csv-record "book" fields)
(map (cut apply make-book <>)
data))))
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