v2.0.0 Beta 9

• Final README for v2.0.0.
• Added tests for remaining README examples.
• Fixed a bug where processing nil fields would raise an exception.
• Fixed a broken test.

v2.0.0 Release

Adds the following features:

• Custom formatters.
• Alignment and padding options.
• Arbitrarily named signature field.
• Custom record classes

Other changes:

• Removes support for parsing CSV files.
• Fixes a bug whereby fields with custom parsers would not have leading or trailing whitespace stripped.

v2.0.0 Beta 8

• Updated the README for the v2.0.0 release.
• Added tests for most of the README examples.
• Fixed a bug whereby fields with custom parsers would not be stripped.

v2.0.0 Beta 7

• Added type option to field definition. This is a shorthand for padding and alignment defaults and can be :alpha (left-justified, space-padded), or :numeric (right-justified, zero-padded).
• Added :center alignment (:centre is permitted as an alias for the benefit of those of us brought up on British English).

definition = Pikelet.define do
  number 0... 3, type:  :numeric          # Right align the output and pad with zeroes.
  name   3...13, align: :center, pad: "." # Centre-align and pad with periods.
end

definition.format([
  { number:  1, name: "Copernicus" },
  { number: 99, name: "Brahe"      }
].map(&OpenStruct.method(:new)))

# => [
#   "001Copernicus",
#   "099..Brahe..."
# ]

v2.0.0 Beta 6

Internal refactoring.

v2.0.0 Beta 5

Moved type_signature declaration to a signature_field option on the base definition.

Pikelet.define signature_field: :type do
  type 0...4

  record "NAME" do
    ...
  end

  record "ADDR" do
    ...
  end
end

Previously type_signature declarations could be made on a per-record basis. This is no longer possible.

The legacy approach of declaring a type_signature as a field will still work.

Pikelet.define do
  type_signature 0...4

  record "NAME" do
    ...
  end

  record "ADDR" do
    ...
  end
end

v2.0.0 Beta 4

Records can now use custom classes.

class Name
  attr_reader :first, :last

  def initialize(first: nil, last: nil)
    @first = first
    @last = last
  end
end

Pikelet.define record_class: Name do
  first  0...10
  last  10...20
end

Here's a slightly more complicated example.

class Name
  attr_reader :first, :last

  def initialize(**attrs)
    @first = attrs[:first]
    @last = attrs[:last]
  end
end

class Address
  attr_reader :street, :city, :postcode, :state, :country

  def initialize(**attrs)
    @street = attrs[:street]
    @city = attrs[:city]
    @postcode = attrs[:postcode]
    @state = attrs[:state]
    @country = attrs[:country]
  end
end

Pikelet.define do
  type_signature :record_type

  record_type 0...4

  record "NAME", record_class: Name do
    first  4...14
    last  14...24
  end

  record "ADDR", record_class: Address do
    street    4...14
    city     14...24
    postcode 24...29
    state    29...39
    country  39...49
  end
end

v2.0.0 Beta 3

With this release an arbitrary field can be used for the type signature.

Previously type_signature was defined as a regular field, but treated specially by Pikelet. This meant, among other things, that the records generated always had a type_signature attribute, which is a bit inelegant. Now you can name your fields however you like and nominate one as the type signature.

Pikelet.define do
  type_signature :record_type # Use 'record_type' as the type signature field

  record_type 0...4

  record "NAME" do
    ...
  end

  record "ADDR" do
    ...
  end
end

Note that the type_signature declaration can precede the declaration of the actual field.

The old type signature syntax (see below) still works, so you do not need to modify any existing definitions.

Pikelet.define do
  type_signature 0...4

  record "NAME" do
    ...
  end

  record "ADDR" do
    ...
  end
end

v2.0.0 Beta 2

In this release we add:

New features

• Custom formatters
• Alignment & padding options

definition = Pikelet.define do
  number    0... 3, align:  :right, pad: "0"                    # Right align the output and pad with zeroes.
  name      3...13, format: :upcase                             # Upcase the value on output.
  password 13...53, format: ->(v) { Digest::SHA1.hexdigest(v) } # Hash the value.
end

definition.format([
  { number:  1, name: "Copernicus", password: "password" },
  { number: 99, name: "Brahe",      password: "sekrit"   }
].map(&OpenStruct.method(:new)))

# => [
#   "001COPERNICUS5baa61e4c9b93f3f0682250b6cf8331b7ee68fd8",
#   "099BRAHE     8d42e738c7adee551324955458b5e2c0b49ee655"
# ]

Changes

• Alignment defaults to :left instead of :right.

v2.0.0 Beta 1

The next release of Pikelet will be capable of formatting flat-file databases for output. As part of this I will be dropping CSV support as it is constraining my options and, as far as I know, nobody is using it. For the time being I want to let it evolve as a pure flat-file database parser. In a future release I may restore CSV support, but I make no promises.

In this release rudimentary formatting is possible.

Example

definition = Pikelet.define do
  type_signature 0...4

  record "NAME" do
    first_name  4...14
    last_name  14...24
  end

  record "ADDR" do
    street_address  4...24
    city           24...44
    postal_code    44...54
    state          54...74
  end
end

records = [
  { type_signature: 'NAME', first_name: "Nicolaus", last_name: 'Copernicus' },
  { type_signature: 'ADDR', street_address: "123 South Street", city: "Nowhereville", postal_code: "45678Y", state: "Someplace" }
].map(&OpenStruct.method(:new))

output = definition.format(records)

# => [
#   "NAME  NicolausCopernicus                                                  ",
#   "ADDR    123 South Street        Nowhereville    45678Y           Someplace"
# ]