"#grid > .core is undefined" when lessc compile bootstrap

Question

i got the following error when i ran lessc bootstrap.less

at less.Parser.parser.parse.i (/Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/js/lib/less/parser.js:385:31): #grid > .core is undefined (Less::ParseError)
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/parser.rb:61:in `block in to_css'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:90:in `block in do_lock'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:88:in `call'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:88:in `Locker'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:88:in `do_lock'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:60:in `lock'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script/v8_context.rb:30:in `exec'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/java_script.rb:26:in `exec'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/lib/less/parser.rb:61:in `to_css'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/gems/less-2.2.2/bin/lessc:99:in `<top (required)>'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/bin/lessc:19:in `load'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/bin/lessc:19:in `<main>'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/bin/ruby_noexec_wrapper:14:in `eval'
from /Users/ftiasch/.rvm/gems/ruby-1.9.3-p374/bin/ruby_noexec_wrapper:14:in `<main>'

i have found this issue. but i have got my lessc upgraded to 1.3.

here is the version:

lessc -v

lessc 1.3.0 (LESS Compiler) [Ruby] 2.2.2

the bootstrap source file are cloned from github.

Answer 1

We need to upgrade less to version 1.3.3.

Example (if you're running less from within node.js)

sudo npm install -g less