If you don't mind slurping the whole file into memory you can do it with regexps. First divide the file into part containing nodes and another one containing edges. Than do a match similar to this:

while($nodepart =~ m/node\s* \{\s* title:\s* "([^"]*)"\s*
    loc\s* \{\s* x:\s* (\d+)\s* y:\s* (\d+)\s* \}\s*
    \}\s*/gx){
            build_the_structure_with_captured_node($1,$2,$3);
}
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And another one for the edges.

Most of languages have some regexp library - so this can work.

Update: The s modifier was not needed - \s matches a newline without it.