tabnas-alchemy 0.1.1

The alchemy grammar plugin and language for the tabnas parsing engine: declarative streaming transducers and renderers.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

; The standard CSV renderer: TableRows in, Text out, in the always-quoted
; RFC 4180 profile (design document sections 13.1 and 13.2). `csv-table`
; is the protocol validator section 13.2 asks for (one schema first, rows
; as wide as it, one end), with the renderer's own refusals: a table of no
; columns, and a delimiter no reader could take. The runtime runs `csv`
; natively when the options record maps onto the renderer's dialect, and
; the differential test proves that path and this text produce the same
; bytes, or fail with the same code.

def csv-options
  record
    entry :delimiter ","
    entry :newline "\r\n"
    entry :header true
    entry :null-text ""
    entry :missing :error

def csv-field [options cell]
  concat
    "\""
    replace-text "\"" "\"\""
      scalar-text options cell
    "\""

def csv-row [options cells]
  concat
    join (get :delimiter options)
      map
        fn [cell]
          csv-field options cell
        cells
    get :newline options

def csv [options events]
  concat-map
    fn [event]
      match event
        case (schema columns)
          if (get :header options)
            csv-row options
              map
                fn [column]
                  get :label column
                columns
            ""
        case (row cells)
          csv-row options cells
        case table-end
          ""
    csv-table options events