Add export JS component and improve some error handling

src/LiveWeb-Bulma/LWBulmaColumns.class.st

@@ -70,7 +70,7 @@ LWBulmaColumns >> oneQuarter: aComponent [
 LWBulmaColumns >> renderOn: h [
  h div: { #class -> 'columns' } with: [ 
 	columns do: [ :c |
-		h div: { #class -> ('column {1}' format: {c value}) } with: [ c key render ]
+		h div: { #class -> ('column {1}' format: {c value}) } with: [ c key render: h ]
 	]
  ]
 ]

src/LiveWeb-Core/LWExportJS.class.st

@@ -0,0 +1,34 @@
+Class {
+	#name : #LWExportJS,
+	#superclass : #LWComponent,
+	#instVars : [
+		'export'
+	],
+	#category : #'LiveWeb-Core'
+}
+
+{ #category : #accessing }
+LWExportJS >> export: nameToCallbackAssociation [
+ export add: nameToCallbackAssociation.
+]
+
+{ #category : #initialization }
+LWExportJS >> initialize [ 
+ super initialize.
+ export := OrderedCollection new.
+]
+
+{ #category : #rendering }
+LWExportJS >> renderOn: h [
+	h script: [ 
+		export do: [ :e |
+			| name cb cbId argNames |
+			name := e key.
+			cb := e value.
+			argNames := ',' join: ((1 to: cb numArgs) collect: [ :i | 'a{1}' format: { i } ]).
+			cbId := ctx registerCallback: cb for: self.
+			h raw: 'function '; raw: name asString; raw: '('; raw: argNames;
+			  raw: '){_lws('; raw: cbId asString; raw: ',['; raw: argNames; raw: '])} '.
+		]
+   ]
+]

src/LiveWeb-Core/LWPageConnection.class.st

@@ -104,7 +104,7 @@ LWPageConnection >> run: aWebSocket [
 
 	[ ws runWith: [ :msg |
 		LWLogEvent debug: '<- ', msg printString.
-		self callback: msg ]] 
+		self tryCallback: msg ]] 
 	on: ConnectionClosed 
 	do: [ 
 		LWLogEvent debug: 'Page disconnected, id: ', page id asString.
@@ -118,3 +118,12 @@ LWPageConnection >> run: aWebSocket [
 LWPageConnection >> send: patches [
 	ws sendMessage: (STONJSON toString: patches)
 ]
+
+{ #category : #'as yet unclassified' }
+LWPageConnection >> tryCallback: message [ 
+ [ self callback: message ]
+ on: Error 
+ do: [ :ex |
+	LWLogEvent error: 'Error in callback processing: ', ex asString
+ ]
+]