This package ensures that only referenced packages are loaded. 2 is referenced by this example and 1 is referenced by 2. 3 and 4 are loaded, but as they aren't used by the page right away, they aren't loaded at the start.

Source files:

Package 1
Package 2
Package 3
Package 4
Package 5 (should never be loaded)

Click this button to run a script that requires package 4:

Defining package "org.jspkg1.scriptloaders.html.scripttag" with namespace "org.jspkg1"
Defining script "packageApply on org.jspkg1.logging.core"
importsmatch = null for package packageApply on org.jspkg1.logging.core
Mapping package "packageApply on org.jspkg1.logging.core" to dependency "org.jspkg1.logging.core"
Need to load package "org.jspkg1.logging.core"
checkCanExecute(packageApply on org.jspkg1.logging.core): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.logging.core): Package "org.jspkg1.logging.core" hasn't been loaded yet
importsmatch = null for package org.jspkg1.scriptloaders.html.scripttag
Defining package "org.jspkg1.packageloaders.simple" with namespace "org.jspkg1"
importsmatch = null for package org.jspkg1.packageloaders.simple
Defining package "org.jspkg1.packageloaders.singlefile" with namespace "org.jspkg1"
importsmatch = null for package org.jspkg1.packageloaders.singlefile
Defining package "org.jspkg1.util.formatting" with namespace "org.jspkg1.util.formatting"
importsmatch = null for package org.jspkg1.util.formatting
Defining package "org.jspkg1.scriptloaders.generic.xmlhttp" with namespace "org.jspkg1.scriptloaders.generic.xmlhttp"
importsmatch = null for package org.jspkg1.scriptloaders.generic.xmlhttp
Defining package "org.jspkg1.loggers.html.debugdiv" with namespace "org.jscore"
importsmatch = /^org\.jspkg1\.util\.formatting$/ for package org.jspkg1.loggers.html.debugdiv
Mapping package "org.jspkg1.loggers.html.debugdiv" to dependency "org.jspkg1.util.formatting"
Need to load package "org.jspkg1.util.formatting"
Defining script "org.jspkg1.tags.htmltags"
importsmatch = null for package org.jspkg1.tags.htmltags
checkCanExecute(org.jspkg1.tags.htmltags): Starting dependency search
checkCanExecute(org.jspkg1.tags.htmltags): All dependencies satisfied
Assigned packageloader "org.jspkg1.packageloaders.singlefile" for package pattern "my.**"
Defining script "Script for initial usings and imports"
importsmatch = null for package Script for initial usings and imports
Mapping package "Script for initial usings and imports" to dependency "org.jspkg1.loggers.html.debugdiv"
Mapping package "Script for initial usings and imports" to dependency "my.test.package.p2"
Need to load package "org.jspkg1.loggers.html.debugdiv"
Testing packageloader /^my.*$/
Need to load package "my.test.package.p2"
Testing packageloader /^my.*$/
Found packageloader match "org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.packageloaders.singlefile"
importsmatch = null for package packageApply on org.jspkg1.packageloaders.singlefile
Mapping package "packageApply on org.jspkg1.packageloaders.singlefile" to dependency "org.jspkg1.packageloaders.singlefile"
Need to load package "org.jspkg1.packageloaders.singlefile"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Initializing package "org.jspkg1.packageloaders.singlefile"
Package "org.jspkg1.packageloaders.singlefile" exported symbol "Loader"
Package "org.jspkg1.packageloaders.singlefile" provided package "org.jspkg1.packageloaders.singlefile"
Checking package "packageApply on org.jspkg1.packageloaders.singlefile"
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.scriptloaders.html.scripttag"
importsmatch = null for package packageApply on org.jspkg1.scriptloaders.html.scripttag
Mapping package "packageApply on org.jspkg1.scriptloaders.html.scripttag" to dependency "org.jspkg1.scriptloaders.html.scripttag"
Need to load package "org.jspkg1.scriptloaders.html.scripttag"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.scriptloaders.html.scripttag): Starting dependency search
checkCanExecute(org.jspkg1.scriptloaders.html.scripttag): Starting dependency search
checkCanExecute(org.jspkg1.scriptloaders.html.scripttag): All dependencies satisfied
Initializing package "org.jspkg1.scriptloaders.html.scripttag"
Package "org.jspkg1.scriptloaders.html.scripttag" exported symbol "Loader"
Package "org.jspkg1.scriptloaders.html.scripttag" provided package "org.jspkg1.scriptloaders.html.scripttag"
Checking package "packageApply on org.jspkg1.scriptloaders.html.scripttag"
checkCanExecute(packageApply on org.jspkg1.scriptloaders.html.scripttag): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.scriptloaders.html.scripttag): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.scriptloaders.html.scripttag"
checkCanExecute(Script for initial usings and imports): Starting dependency search
checkCanExecute(org.jspkg1.loggers.html.debugdiv): Starting dependency search
checkCanExecute(org.jspkg1.util.formatting): Starting dependency search
checkCanExecute(org.jspkg1.util.formatting): All dependencies satisfied
Initializing package "org.jspkg1.util.formatting"
Package "org.jspkg1.util.formatting" exported symbol "Formatting"
Package "org.jspkg1.util.formatting" provided package "org.jspkg1.util.formatting"
Checking package "org.jspkg1.loggers.html.debugdiv"
checkCanExecute(org.jspkg1.loggers.html.debugdiv): Starting dependency search
checkCanExecute(org.jspkg1.loggers.html.debugdiv): All dependencies satisfied
Initializing package "org.jspkg1.loggers.html.debugdiv"
Importing symbol "org.jspkg1.util.formatting.Formatting" into package "org.jspkg1.loggers.html.debugdiv"
Package "org.jspkg1.loggers.html.debugdiv" imports package "org.jspkg1.util.formatting"
Imported symbol Formatting
Package "org.jspkg1.loggers.html.debugdiv" exported symbol "Logger"
Package "org.jspkg1.loggers.html.debugdiv" provided package "org.jspkg1.logging.core"
Checking package "packageApply on org.jspkg1.logging.core"
checkCanExecute(packageApply on org.jspkg1.logging.core): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.logging.core): All dependencies satisfied
Importing symbol "org.jscore.Logger" into package "packageApply on org.jspkg1.logging.core"
Package "org.jspkg1.loggers.html.debugdiv" provided package "org.jspkg1.loggers.html.debugdiv"
Checking package "Script for initial usings and imports"
checkCanExecute(Script for initial usings and imports): Starting dependency search
checkCanExecute(Script for initial usings and imports): Package "my.test.package.p2" hasn't been loaded yet
checkCanExecute(Script for initial usings and imports): Package "my.test.package.p2" hasn't been loaded yet
Defining package "my.test.package.p1" with namespace "my.test"
importsmatch = null for package my.test.package.p1
Mapping package "my.test.package.p1" to dependency "my.test.package.onload"
Need to load package "my.test.package.onload"
Testing packageloader /^my.*$/
Found packageloader match "org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.packageloaders.singlefile"
importsmatch = null for package packageApply on org.jspkg1.packageloaders.singlefile
Mapping package "packageApply on org.jspkg1.packageloaders.singlefile" to dependency "org.jspkg1.packageloaders.singlefile"
Need to load package "org.jspkg1.packageloaders.singlefile"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.packageloaders.singlefile"
Defining package "my.test.package.p2" with namespace "my.test"
importsmatch = null for package my.test.package.p2
Mapping package "my.test.package.p2" to dependency "my.test.package.onload"
Mapping package "my.test.package.p2" to dependency "my.test.package.p1"
Need to load package "my.test.package.p1"
Testing packageloader /^my.*$/
Found packageloader match "org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.packageloaders.singlefile"
importsmatch = null for package packageApply on org.jspkg1.packageloaders.singlefile
Mapping package "packageApply on org.jspkg1.packageloaders.singlefile" to dependency "org.jspkg1.packageloaders.singlefile"
Need to load package "org.jspkg1.packageloaders.singlefile"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.packageloaders.singlefile"
checkCanExecute(my.test.package.p2): Starting dependency search
checkCanExecute(my.test.package.p2): Package "my.test.package.onload" hasn't been loaded yet
Defining package "my.test.package.p3" with namespace "my.test"
importsmatch = null for package my.test.package.p3
Mapping package "my.test.package.p3" to dependency "my.test.package.onload"
Mapping package "my.test.package.p3" to dependency "my.test.package.p2"
Defining package "my.test.package.p4" with namespace "my.test"
importsmatch = null for package my.test.package.p4
Mapping package "my.test.package.p4" to dependency "my.test.package.onload"
Mapping package "my.test.package.p4" to dependency "my.test.package.p3"
Need to load package "my.test.package.p3"
Testing packageloader /^my.*$/
Found packageloader match "org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.packageloaders.singlefile"
importsmatch = null for package packageApply on org.jspkg1.packageloaders.singlefile
Mapping package "packageApply on org.jspkg1.packageloaders.singlefile" to dependency "org.jspkg1.packageloaders.singlefile"
Need to load package "org.jspkg1.packageloaders.singlefile"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.packageloaders.singlefile"
Defining package "my.test.package.p5" with namespace "my.test"
importsmatch = null for package my.test.package.p5
Mapping package "my.test.package.p5" to dependency "my.test.package.onload"
Mapping package "my.test.package.p5" to dependency "my.test.package.p4"
Need to load package "my.test.package.p4"
Testing packageloader /^my.*$/
Found packageloader match "org.jspkg1.packageloaders.singlefile"
Defining script "packageApply on org.jspkg1.packageloaders.singlefile"
importsmatch = null for package packageApply on org.jspkg1.packageloaders.singlefile
Mapping package "packageApply on org.jspkg1.packageloaders.singlefile" to dependency "org.jspkg1.packageloaders.singlefile"
Need to load package "org.jspkg1.packageloaders.singlefile"
Testing packageloader /^my.*$/
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): Starting dependency search
checkCanExecute(packageApply on org.jspkg1.packageloaders.singlefile): All dependencies satisfied
Importing symbol "org.jspkg1.Loader" into package "packageApply on org.jspkg1.packageloaders.singlefile"
Defining package "my.test.package.onload" with namespace "my.test.package.onload"
importsmatch = null for package my.test.package.onload
checkCanExecute(my.test.package.onload): Starting dependency search
checkCanExecute(my.test.package.onload): All dependencies satisfied
Initializing package "my.test.package.onload"
Package "my.test.package.onload" provided package "my.test.package.onload"
Checking package "my.test.package.p1"
checkCanExecute(my.test.package.p1): Starting dependency search
checkCanExecute(my.test.package.p1): All dependencies satisfied
Initializing package "my.test.package.p1"
Package "my.test.package.p1" provided package "my.test.package.p1"
Checking package "my.test.package.p2"
checkCanExecute(my.test.package.p2): Starting dependency search
checkCanExecute(my.test.package.p2): All dependencies satisfied
Initializing package "my.test.package.p2"
Package "my.test.package.p2" provided package "my.test.package.p2"
Checking package "Script for initial usings and imports"
checkCanExecute(Script for initial usings and imports): Starting dependency search
checkCanExecute(Script for initial usings and imports): All dependencies satisfied
Importing symbol "org.jscore.Logger" into package "Script for initial usings and imports"
Checking package "my.test.package.p3"
Checking package "my.test.package.p2"
Checking package "my.test.package.p3"
Checking package "my.test.package.p4"
Checking package "my.test.package.p5"