meaning of | in scheme

[Damien Mattei]

i'm annoying with some | | that appear sometimes in my parser but i do
not know where they came from

#|kawa:2|# (|≠| 2 2)
#f
#|kawa:3|# |≠|
#<procedure ≠>
#|kawa:4|# |java.lang.Math:random|
/dev/tty:4:1: warning - no declaration seen for java.lang.Math:random
/dev/tty:4:1: unbound location: java.lang.Math:random
    at gnu.mapping.DynamicLocation.get(DynamicLocation.java:36)
    at atInteractiveLevel-35.run(tty:4)
    at gnu.expr.ModuleExp.evalModule2(ModuleExp.java:290)
    at gnu.expr.ModuleExp.evalModule(ModuleExp.java:211)
    at kawa.Shell.run(Shell.java:289)
    at kawa.Shell.run(Shell.java:196)
    at kawa.Shell.run(Shell.java:183)
    at kawa.repl.processArgs(repl.java:724)
    at kawa.repl.main(repl.java:830)
#|kawa:5|# java.lang.Math:random
Type double java.lang.Math.random()
#|kawa:6|# |sin|
#<procedure sin>

i can not remember exactly why some symbols are sometimes in | | in
scheme, this was not a problem with procedures but it behavior bad
with java method imported in kawa, see the error.

and i can not find where it is generated in the parser (attached)

why it does not offend scheme procedure? (and why is it a problem with
java imported methods)

any idea?
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