LOOKY LOOKY LOOKY I did it :)

[PATTON, BILLY \(SBCSI\)]

I need to create new names from a list which pointed to another list
PROJECTS   := lde ldg ldm ldf ldw lbf ldb
BB_lde     := a
BB_ldg     := b c
BB_ldm     := d e f
BB_ldf     := g h i j
BB_ldw     := k l n m o
BB_lbf     := p q r s t u
BB_ldb     := v w x y z aa ab
MKDIR_BB   := $(foreach proj,${PROJECTS},$(foreach
bb,$(BB_${proj}),$(addprefix ${proj}_,$(bb))))
# need results lde_a ldg_b ldg_c ldm_d ldm_e ldm_f ldf_g ldf_h ldg_i ...

and got
MKDIR_BB = 'lde_a ldg_b ldg_c ldm_d ldm_e ldm_f ldf_g ldf_h ldf_i ldf_j 
ldw_k ldw_l ldw_n ldw_m ldw_o lbf_p lbf_q lbf_r lbf_s
 lbf_t lbf_u ldb_v ldb_w ldb_x ldb_y ldb_z ldb_aa ldb_ab'


Everything :) I was after