Rosetta Code

Align columns

Align Rosetta Code's dollar-delimited sample text into left, right, and centered columns.

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Sourcerosettacode/popular/align_columns.vibe
def trim_trailing_dollars(line: string) -> string
  while line.end_with?("$")
    line = line.delete_suffix("$")
  end
  line
end

def split_columns(line: string) -> array<string>
  trim_trailing_dollars(line).split("$")
end

def column_widths(rows: array<array<string>>) -> array<int>
  widths: array<int> = []
  rows.each { |row|
    column = 0
    while column < row.length
      while widths.length <= column
        widths = widths + [0]
      end
      current = widths[column]
      width = row.fetch(column).length
      if current == nil || width > current
        widths[column] = width
      end
      column = column + 1
    end
  }
  widths
end

def spaces(count: int) -> string
  buffer = ""
  index = 0
  while index < count
    buffer = buffer + " "
    index = index + 1
  end
  buffer
end

def left_justify(text: string, width: int) -> string
  text + spaces(width - text.length)
end

def right_justify(text: string, width: int) -> string
  spaces(width - text.length) + text
end

def center_justify(text: string, width: int) -> string
  padded = text
  add_left = false
  while padded.length < width
    if add_left
      padded = " " + padded
      add_left = false
    else
      padded = padded + " "
      add_left = true
    end
  end
  padded
end

def justify(text: string, width: int, alignment: string) -> string
  if alignment == "left"
    left_justify(text, width)
  elsif alignment == "right"
    right_justify(text, width)
  else
    center_justify(text, width)
  end
end

def render_row(row: array<string>, widths: array<int>, alignment: string) -> string
  line = ""
  column = 0
  while column < widths.length
    value = ""
    if column < row.length
      value = row.fetch(column)
    end
    line = line + justify(value, widths.fetch(column), alignment)
    if column < widths.length - 1
      line = line + " "
    end
    column = column + 1
  end
  line.rstrip
end

def align_columns(lines: array<string>, alignment: string) -> array<string>
  rows: array<array<string>> = []
  lines.each { |line|
    rows = rows + [split_columns(line)]
  }

  widths = column_widths(rows)
  aligned: array<string> = []
  rows.each { |row|
    aligned = aligned + [render_row(row, widths, alignment)]
  }
  aligned
end

def sample_lines -> array<string>
  [
    "Given$a$text$file$of$many$lines,$where$fields$within$a$line$",
    "are$delineated$by$a$single$'dollar'$character,$write$a$program",
    "that$aligns$each$column$of$fields$by$ensuring$that$words$in$each$",
    "column$are$separated$by$at$least$one$space.",
    "Further,$allow$for$each$word$in$a$column$to$be$either$left$",
    "justified,$right$justified,$or$center$justified$within$its$column."
  ]
end

def run -> { center: string, left: string, right: string, widths: array<int> }
  lines = sample_lines
  rows: array<array<string>> = []
  lines.each { |line|
    rows = rows + [split_columns(line)]
  }
  widths = column_widths(rows)
  {
    widths: widths,
    left: render_row(rows.fetch(0), widths, "left"),
    right: render_row(rows.fetch(0), widths, "right"),
    center: render_row(rows.fetch(0), widths, "center")
  }
end

Output

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