regex simplification

src/network_configuration_parser.cr

@@ -32,8 +32,8 @@ class NetworkConfigurationParser
 				up = true
 			when /^description/
 				description = /^description (.+)/.match(line).try &.[1]
-			when /^inet6? alias .*/
-				ipstr = /^inet6? alias ([a-f0-9:.\/]+)/.match(line).try &.[1]
+			when /^inet6? alias (?<ip>[a-f0-9:.\/]+)/
+				ipstr = $~["ip"]
 				if ipstr.nil?
 					puts "wrong IP address alias, line #{line}"
 					next
@@ -50,8 +50,8 @@ class NetworkConfigurationParser
 				# IP address is autoconfigured
 				main_ip_v6 = Autoconfiguration.new
 
-			when /^inet6? .*/
-				ipstr = /^inet6? ([a-f0-9:.\/]+)/.match(line).try &.[1]
+			when /^inet6? (?<ip>[a-f0-9:.\/]+)/
+				ipstr = $~["ip"]
 				if ipstr.nil?
 					puts "wrong IP address, line #{line}"
 					next
@@ -62,10 +62,10 @@ class NetworkConfigurationParser
 					main_ip_v6 = IPAddress.parse ipstr
 				end
 
-			when /^join [^ \t]+ wpakey .*/
+			when /^join (?<ssid>[^ \t]+) wpakey (?<wpakey>[^ \t]+)/
 				# WPA2-PSK, other security mechanisms are not supported, yet
-				ssid = /^join ([^ \t]+)/.match(line).try &.[1]
-				wpakeystr = /^join [^ \t]+ wpakey ([^ \t]+)/.match(line).try &.[1]
+				ssid = $~["ssid"]
+				wpakeystr = $~["wpakey"]
 
 				if ssid.nil?
 					puts "wrong SSID in line: #{line}"
@@ -80,31 +80,20 @@ class NetworkConfigurationParser
 				new_ap = WirelessAPSetup.new ssid, WirelessAPSetup::WPA.new(wpakeystr)
 				wireless_networks[ssid] = new_ap
 
-			when /^network [^ \t]+ inet6 autoconf/
-				ssid = /^network ([^ \t]+)/.match(line).try &.[1]
-				ipstr = /^network [^ \t]+ inet6? ([^ \t]+)/.match(line).try &.[1]
+			when /^network (?<ssid>[^ \t]+) inet6 autoconf/
+				ssid = $~["ssid"]
 
 				if ssid.nil?
 					puts "wrong SSID in line: #{line}"
 					next
 				end
 
-				if ipstr.nil?
-					puts "wrong ip address in line: #{line}"
-					next
-				end
-
 				access_point = wireless_networks[ssid].not_nil!
 				access_point.main_ip_v6 = Autoconfiguration.new
 
-			when /^network [^ \t]+ inet6? .*/
-				ssid = nil
-				ipstr = nil
-
-				/^network (?<ssid>[^ \t]+) inet6? (?<ip>[^ \t]+)/.match(line).try do |m|
-					ssid = m["ssid"]
-					ipstr = m["ip"]
-				end
+			when /^network (?<ssid>[^ \t]+) inet6? (?<ip>[^ \t]+)/
+				ssid = $~["ssid"]
+				ipstr = $~["ip"]
 
 				if ssid.nil?
 					puts "wrong SSID in line: #{line}"
@@ -127,8 +116,8 @@ class NetworkConfigurationParser
 					puts "wrong ip address in line: #{line} (neither ipv4 or ipv6)"
 				end
 
-			when /^network [^ ]+ dhcp6?/
-				ssid = /^network (?<ssid>[^ \t]+)/.match(line).try &.["ssid"]
+			when /^network (?<ssid>[^ \t]+) dhcp6?/
+				ssid = $~["ssid"]
 
 				if ssid.nil?
 					puts "wrong SSID in line: #{line}"
@@ -145,14 +134,9 @@ class NetworkConfigurationParser
 					puts "wrong dhcp instruction in line: #{line}"
 				end
 
-			when /^network [^ ]+ dns .*/
-				ssid = nil
-				ipstr = nil
-
-				/^network (?<ssid>[^ \t]+) dns (?<ip>[^ \t]+)/.match(line).try do |m|
-					ssid = m["ssid"]
-					ipstr = m["ip"]
-				end
+			when /^network (?<ssid>[^ \t]+) dns (?<ip>[^ \t]+)/
+				ssid = $~["ssid"]
+				ipstr = $~["ip"]
 
 				if ssid.nil?
 					puts "wrong SSID in line: #{line}"
@@ -168,15 +152,11 @@ class NetworkConfigurationParser
 				ipaddr = IPAddress.parse ipstr
 				access_point.dns.addresses << ipaddr.to_s
 
-			when /^mtu [0-9]+/
-				mtu = /^mtu ([0-9]+)/.match(line).try &.[1].to_i
+			when /^mtu (?<mtu>[0-9]+)/
+				mtu = $~["mtu"].to_i
 
-			when /^dns [^ \t]+/
-				ipstr = nil
-
-				/^dns (?<ip>[^ \t]+)/.match(line).try do |m|
-					ipstr = m["ip"]
-				end
+			when /^dns (?<ip>[^ \t]+)/
+				ipstr = $~["ip"]
 
 				if ipstr.nil?
 					puts "wrong ip address in line: #{line}"