public static IEnumerable <CodeInstruction> AddRegionBefore(this IEnumerable <CodeInstruction> code, Func <CodeInstruction, bool>[] before,
Func <CodeInstruction[], IEnumerable <CodeInstruction> > region)
{
if (code is null)
{
throw new ArgumentNullException(nameof(code));
}
if (before is null)
{
throw new ArgumentNullException(nameof(before));
}
if (region is null)
{
throw new ArgumentNullException(nameof(region));
}
if (before.Length is 0)
{
throw new ArgumentException($"{nameof(before)} cannot be empty.", nameof(before));
}
if (Array.Exists(before, b => b is null))
{
throw new ArgumentException($"Delegates in {nameof(before)} cannot be null.", nameof(before));
}
return(AddRegionBefore2());
IEnumerable <CodeInstruction> AddRegionBefore2()
{
SearchState state = SearchState.Searching;
int current = 0;
CodeInstruction[] matches = new CodeInstruction[before.Length];
foreach (CodeInstruction instr in code)
{
if (state == SearchState.Passed)
{
yield return(instr);
}
else if (state == SearchState.Searching)
{
if (before[current](instr))
{
matches[current] = instr;
if (++current == before.Length)
{
state = SearchState.Passed;
CodeInstruction[] arr = new CodeInstruction[matches.Length];
matches.CopyTo(arr, 0);
IEnumerable <CodeInstruction> added = region(arr);
if (added is null)
{
throw new ArgumentException($"{nameof(region)} cannot return null.");
}
foreach (CodeInstruction instr2 in added)
{
if (instr2 is null)
{
throw new ArgumentException($"Collection returned by {nameof(region)} cannot contain null.", nameof(region));
}
yield return(new CodeInstruction(instr2));
}
for (int i = 0; i < current; i++)
{
yield return(matches[i]);
}
}
}
else
{
if (current > 0)
{
for (int i = 0; i < current; i++)
{
yield return(matches[i]);
}
current = 0;
}
yield return(instr);
}
}
}
}
}
public static IEnumerable <CodeInstruction> AddRegionAfter(this IEnumerable <CodeInstruction> code, Func <CodeInstruction, bool>[] after,
Func <CodeInstruction[], IEnumerable <CodeInstruction> > region)
{
if (code is null)
{
throw new ArgumentNullException(nameof(code));
}
if (after is null)
{
throw new ArgumentNullException(nameof(after));
}
if (region is null)
{
throw new ArgumentNullException(nameof(region));
}
if (after.Length is 0)
{
throw new ArgumentException($"{nameof(after)} cannot be empty.", nameof(after));
}
if (Array.Exists(after, a => a is null))
{
throw new ArgumentException($"Delegates in {nameof(after)} cannot be null.", nameof(after));
}
return(AddRegionAfter2());
IEnumerable <CodeInstruction> AddRegionAfter2()
{
SearchState state = SearchState.Searching;
int current = 0;
CodeInstruction[] matches = new CodeInstruction[after.Length];
foreach (CodeInstruction instr in code)
{
if (state == SearchState.Passed)
{
yield return(instr);
}
else if (state == SearchState.Searching)
{
yield return(instr);
if (after[current](instr))
{
matches[current] = instr;
if (++current == after.Length)
{
state = SearchState.Passed;
CodeInstruction[] arr = new CodeInstruction[matches.Length];
matches.CopyTo(arr, 0);
IEnumerable <CodeInstruction> added = region(arr);
if (added is null)
{
throw new ArgumentException($"{nameof(region)} cannot return null.");
}
foreach (CodeInstruction instr2 in added)
{
if (instr2 is null)
{
throw new ArgumentException($"Collection returned by {nameof(region)} cannot contain null.", nameof(region));
}
yield return(new CodeInstruction(instr2));
}
}
}
else
{
current = 0;
}
}
}
if (state == SearchState.Searching)
{
throw new InvalidOperationException("Could not match the after region.");
}
}
}
