Posexional.Row (posexional v1.2.0)

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this module represent a row in a positional file

Summary

Functions

merge fields from another row

finds a field in the row by its name

calculate the row total length based on the passed fields

Given a row and a field name calculate the field offset

read a positional file row and convert it back to a keyword list of values

outputs a row

Types

t()

@type t() :: %Posexional.Row{
  fields: term(),
  name: term(),
  row_guesser: term(),
  separator: term(),
  struct_module: term()
}

Functions

add_field(row, field)

@spec add_field(
  t(),
  struct()
) :: t()

add_fields(row, fields)

@spec add_fields(t(), []) :: t()

fields_from(to, row)

@spec fields_from(t(), t()) :: t()

merge fields from another row

find_field(row, name)

@spec find_field(t(), atom()) :: Posexional.Field.Value.t()

finds a field in the row by its name

Examples

iex> Posexional.Row.new(:row_test, []) |> Posexional.Row.find_field(:test)
nil

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test, 5)]) |> Posexional.Row.find_field(:test)
Posexional.Field.Value.new(:test, 5)

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test, 5), Posexional.Field.Value.new(:test2, 5)])
...>   |> Posexional.Row.find_field(:test2)
Posexional.Field.Value.new(:test2, 5)

length(row)

@spec length(t()) :: integer()

calculate the row total length based on the passed fields

Examples

iex> Posexional.Row.new(:row_test, [])
...>   |> Posexional.Row.length
0

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test1, 10), Posexional.Field.Value.new(:test2, 20)])
...>   |> Posexional.Row.length
30

manage_counters(row, counters)

@spec manage_counters(t(), [{atom(), pid()}]) :: t()

new(name, fields, opts \\ [])

@spec new(atom(), [struct()], Keyword.t()) :: t()

offset(row, field_name)

@spec offset(t(), atom()) :: integer()

Given a row and a field name calculate the field offset

Examples

iex> Posexional.Row.new(:test, [Posexional.Field.Value.new(:test1, 10), Posexional.Field.Value.new(:test2, 20)])
...>     |> Posexional.Row.offset(:test1)
1

iex> Posexional.Row.new(:test, [Posexional.Field.Value.new(:test1, 10), Posexional.Field.Value.new(:test2, 20)])
...>    |> Posexional.Row.offset(:test2)
11

iex> Posexional.Row.new(:test, [Posexional.Field.Value.new(:test1, 10), Posexional.Field.Value.new(:test2, 20)])
...>     |> Posexional.Row.offset(:test_not_existent)
** (ArgumentError) the field test_not_existent doesn't exists

iex> Posexional.Row.new(:test, [])
...>     |> Posexional.Row.offset(:test)
nil

read(row, content)

@spec read(t(), binary()) :: Keyword.t()

read a positional file row and convert it back to a keyword list of values

write(row, values)

@spec write(t(), Keyword.t()) :: {atom(), binary()}

outputs a row

Examples

iex> Posexional.Row.new(:row_test, []) |> Posexional.Row.write([test: "test"])
{:ok, ""}

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test1, 5), Posexional.Field.Value.new(:test2, 10)])
...>   |> Posexional.Row.write([test1: "test1", test2: "test2"])
{:ok, "test1test2     "}

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test1, 5), Posexional.Field.Value.new(:test2, 10)])
...>   |> Posexional.Row.write([test1: "test1", non_existent: "test2"])
{:ok, "test1          "}

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test1, 6)])
...>   |> Posexional.Row.write([test1: "test1", not_configured: "test2"])
{:ok, "test1 "}

iex> Posexional.Row.new(:row_test, [Posexional.Field.Value.new(:test1, 5)])
...>   |> Posexional.Row.write([not_configured: "test2", another: "test3"])
{:ok, "     "}

iex> Posexional.Row.new(:row_test, [Posexional.Field.Empty.new(5)])
...>   |> Posexional.Row.write([])
{:ok, "     "}