re = /\(\s*;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?\s*(?:;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?(?:\s*;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?)*)?\s*(?:\((?:;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?(?:\s*;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?)*)?\)(?:\((?:;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?(?:\s*;(?:[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*(?:\s*[A-Z](?:\s*[A-Z])*\s*\[(?:\\\]|[^\]])*\](?:\s*\[(?:\\\]|[^\]])*\])*)*)?)*)?\))*)?\s*\)/
str = '(;GM[1]FF[4]CA[UTF-8]AP[Sabaki:0.52.2]KM[6.5]SZ[19]DT[2023-12-25];B[pd];W[dd];B[pq];W[dp])
(;GM[1]FF[4]CA[UTF-8]AP[Sabaki:0.52.2]KM[6.5]SZ[19]DT[2023-12-25];B[pd];W[dd](;B[pq];W[dp])(;B[dp];W[pp]))
(;GM[1]FF[4]CA[UTF-8]AP[Sabaki:0.52.2]KM[6.5]SZ[19]DT[2023-12-25];B[pd];W[dd](;B[pq];W[dp])(;B[dp];W[pp];PL[B]AE[jk]AB[jj]AW[ji];B[jq]))
(;GM[1]FF[4]CA[UTF-8]AP[Sabaki:0.52.2]KM[6.5]SZ[19]DT[2023-12-25];B[pd]C[Comment on move.];W[dd](;B[pq];W[dp])(;B[dp];W[pp];PL[B]AE[jk]AB[jj]AW[ji]C[Comment on editing.];B[jq]))'
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html