Read file, split line, tables of tables

Tables and the table library. example from a Well House Consultants training course
More on Tables and the table library. [link]

This example is described in the following article(s):
• Lua - using modules to add your own utilities - [link]

Source code: sf3 Module: U105

--[[
Read file, split line, tables of tables
]]

fh = io.open("/Users/grahamellis/landreg/data/rstats2014.xyz","r")

places = {}

while true do
        lyne = fh.read(fh)
        if not lyne then break end

        -- Let's split the line into tab delimited fields

        parts = {}
        at = 1
        while true do
        tabby = string.find(lyne,'\t',at)
        if not tabby then
                segment = string.sub(lyne,at,#lyne)
        else
                segment = string.sub(lyne,at,tabby-1)
        end
        parts[#parts+1] = segment
        if not tabby then break end
        at = tabby + 1
        end

        -- and add the split line (now in a table) to the main table

        places[#places+1] = parts
end

print(#places)
for k,v in ipairs(places) do
        passengers = tonumber(v[#v])
        if passengers and passengers < 1500 then
                print (string.format("%4d %3s %30s %6d",k,v[2],v[7],v[#v]))
        end
end

print(places[1234][6])

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