public void MaybeStackItemTest()
{
var stack = new MaybeStack <string>();
stack.Push("alpha");
stack.Push("bravo");
stack.Push("charlie");
if (stack.Item(0).If(out var item, out var exception))
{
Console.WriteLine(item);
}
else
{
Console.WriteLine(exception.Message);
}
if (stack.Item(-1).If(out item, out exception))
{
Console.WriteLine(item);
}
else
{
Console.WriteLine(exception.Message);
}
}
static Scraper()
{
scraperStack = new MaybeStack <Scraper>();
}
public Result <Configuration> Parse()
{
var rootGroup = new Group("_$root");
var stack = new MaybeStack <IConfigurationItem>();
stack.Push(rootGroup);
Maybe <Group> peekGroup()
{
return
(from parentItem in stack.Peek()
from parentGroup in parentItem.IfCast <Group>()
select parentGroup);
}
Maybe <Group> popGroup()
{
return
(from parentItem in stack.Pop()
from parentGroup in parentItem.IfCast <Group>()
select parentGroup);
}
Result <(string newSource, string str)> getString(string source)
{
if (source.Matches("^ /s* /[quote]; f").If(out var result))
{
var quote = result.FirstGroup[0];
return(getQuotedString(source.Drop(result.Length), quote));
}
else if (source.Matches("^ /s* /(-[/r /n]*) ('/r/n')?; f").If(out result))
{
var foundReturn = false;
var builder = new StringBuilder();
for (var i = 0; i < source.Length; i++)
{
var current = source[i];
switch (current)
{
case ';':
return((source.Drop(i + 1), builder.ToString()).Success());
case ']' or '#':
return((source.Drop(i), builder.ToString()).Success());
case '\r' or '\n':
foundReturn = true;
break;
default:
if (foundReturn)
{
return((source.Drop(i - 1), builder.ToString()).Success());
}
else
{
builder.Append(current);
}
break;
}
}
return((string.Empty, builder.ToString()).Success());
}
else
{
return("Couldn't determine string".Failure <(string, string)>());
}
}
public override bool Evaluate(string input)
{
index = State.Position;
var current = input.Skip(index);
if (!current.IsMatch("['()[]{}']"))
{
length = current.Length;
return(true);
}
if (!current.IsMatch("^ ['([{']"))
{
return(false);
}
var stack = new MaybeStack <char>();
for (var i = index; i < input.Length; i++)
{
var currentChar = input[i];
switch (currentChar)
{
case '(':
stack.Push(')');
break;
case '{':
stack.Push('}');
break;
case '[':
stack.Push(']');
break;
case ')':
case '}':
case ']':
var previous = stack.Pop();
if (previous.IsSome)
{
if (previous.Value != currentChar)
{
return(false);
}
if (stack.Count == 0)
{
length = i - index + 1;
return(true);
}
}
else
{
return(false);
}
break;
}
}
if (stack.Count > 0)
{
return(false);
}
length = current.Length;
return(true);
}
