Spaces disallowed in branch grafts

[armatthews]

The following should be allowed, but instead gives "ERROR: Illegal character at start of branch reference name", due to the space between "Branch:" and "pathA".

task First > out :: p=(Branch: pathA=$a pathB=$b) { echo $p > $out }
task Second < in=$out@First[Branch: pathA] {}
global {
a=1
b=2
}

[jhclark]

@dowobeha This is one for you. At first glance, this one looks easy to pull off.