how to process multiple data files using R loop

I have 16 files and would like to check the information of their first two lines, what I did: 

ls(pattern="P_")
 [1] "P_3_utr_source_data"               "P_5_utr_source_data"              
 [3] "P_exon_per_gene_cds_source_data"   "P_exon_per_gene_source_data"      
 [5] "P_exon_source_data"                "P_first_exon_oncds_source_data"   
 [7] "P_first_intron_oncds_source_data"  "P_first_intron_ongene_source_data"
 [9] "P_firt_exon_ongene_source_data"    "P_gene_cds_source_data"           
[11] "P_gene_source_data"                "P_intron_source_data"             
[13] "P_last_exon_oncds_source_data"     "P_last_exon_ongene_source_data"   
[15] "P_last_intron_oncds_source_data"   "P_last_intron_ongene_source_data" 

The results from `ls()` are not actual R names but rather are character vectors. To "promote" a character value to an R language-name you need the `get` function:

for(i in ls(pattern="P_")){head(i, 2)}

for(i in ls(pattern="P_")){ head(get(i), 2)}  # Should work.

David.
It obviously does not work since nothing came out

What I would like to see for the output is :

head(P_3_utr_source_data,2)
  V1
1  1
2  1
head(P_5_utr_source_data,2)
  V1
1  1
2  1

.

.
.

Could anybody help me with this?

Thank you very much for your time:)
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David Winsemius
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how to process multiple data files using R loop

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