IDL syntax highlighting in Notepad++
EDIT: Here's the xml:
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<Keywords name="Words1">if then else for do while repeat until break case switch common continue exit return goto help message print read retall stop</Keywords>
<Keywords name="Words2">a_correlate abs acos adapt_hist_equal alog alog10 amoeba arg_present arra_equal array_indices ascii_template asin assoc atan beseli beselj besel k besely beta bilinear bin_date binary_template dinfgen dinomial blk_con broyden bytarr byte bytscl c_correlate call_external call_function ceil chebyshev check_math chisqr_cvf chisqr_pdf choldc cholsol cindgen clust_wts cluster color_quan colormap_applicable comfit complex complexarr complexround compute_mesh_normals cond congrid conj convert_coord convol coord2to3 correlate cos cosh cramer create_struct crossp crvlength ct_luminance cti_test curvefit cv_coord cvttobm cw_animate cw_arcball cw_bgroup cw_clr_index cw_colorsel cw_defroi cw_field cw_filesel cw_form cw_fslider cw_light_editor cw_orient cw_palette_editor cw_pdmenu cw_rgbslider cw_tmpl cw_zoom dblarr dcindgen dcomplexarr defroi deriv derivsig determ diag_matrix dialog_message dialog_pickfile pialog_printersetup dialog_printjob dialog_read_image dialog_write_image digital_filter dilate dindgen dist double eigenql eigenvec elmhes eof erode erf erfc erfcx execute exp expand_path expint extrac extract_slice f_cvf f_pdf factorial fft file_basename file_dirname file_expand_path file_info file_same file_search file_test file_which filepath findfile findgen finite fix float floor fltarr format_axis_values fstat fulstr fv_test fx_root fz_roots gamma gauss_cvf gauss_pdf gauss2dfit gaussfit gaussint get_drive_list get_kbrd get_screen_size getenv grid_tps grid3 griddata gs_iter hanning hdf_browser hdf_read hilbert hist_2d hist_equal histogram hough hqr ibeta identity idl_validname idlitsys_createtool igamma imaginary indgen int_2d int_3d int_tabulated intarr interpol interpolate invert ioctl ishft julday keword_set krig2d kurtosis kw_test l64indgen label_date label_region ladfit laguerre la_cholmprove la_cholsol la_Determ la_eigenproblem la_eigenql la_eigenvec la_elmhes la_gm_linear_model la_hqr la_invert la_least_square_equality la_least_squares la_linear_equation la_lumprove la_lusol la_trimprove la_trisol leefit legendre linbcg lindgen linfit ll_arc_distance lmfit lmgr lngamma lnp_test locale_get logical_and logical_or logical_true lon64arr lonarr long long64 lsode lu_complex lumprove lusol m_correlate machar make_array map_2points map_image map_patch map_proj_forward map_proj_init map_proj_inverse matrix_multiply matrix_power max md_test mean meanabsdev median memory mesh_clip mesh_decimate mesh_issolid mesh_merge mesh_numtriangles mesh_smooth mesh_surfacearea mesh_validate mesh_volume min min_curve_surf moment morph_close morph_distance morph_gradient morph_histormiss morph_open morph_thin morph_tophat mpeg_open msg_cat_open n_elements n_params n_tags newton norm obj_class obj_isa obj_new obj_valid objarr p_correlate path_sep pcomp pnt_line polar_surface poly poly_2d poly_area poly_fit polyfillv ployshade primes product profile profiles project_vol ptr_new ptr_valid ptrarr qgrid3 qromb qromo qsimp query_bmp query_dicom query_image query_jpeg query_mrsid query_pict query_png query_ppm query_srf query_tiff query_wav r_correlate r_test radon randomn randomu ranks read_ascii read_binary read_bmp read_dicom read_image read_mrsid read_png read_spr read_sylk read_tiff read_wav read_xwd real_part rebin recall_commands recon3 reform region_grow regress replicate reverse rk4 roberts rot rotate round routine_info rs_test s_test savgol search2d search3d sfit shift shmdebug shmvar simplex sin sindgen sinh size skewness smooth sobel sort sph_scat spher_harm spl_init spl_interp spline spline_p sprsab sprsax sprsin sprstp sqrt standardize stddev strarr strcmp strcompress stregex string strjoin strlen strlowcase strmatch strmessage strmid strpos strsplit strtrim strupcase svdfit svsol swap_endian systime t_cvf t_pdf tag_names tan tanh temporary tetra_clip tetra_surface tetra_volume thin timegen tm_test total trace transpose tri_surf trigrid trisol ts_coef ts_diff ts_fcast ts_smooth tvrd uindgen unit uintarr ul64indgen ulindgen ulon64arr ulonarr ulong ulong64 uniq value_locate variance vert_t3d voigt voxel_proj warp_tri watershed where widget_actevix widget_base widget_button widget_combobox widget_draw widget_droplist widget_event widget_info widget_label widget_list widget_propertsheet widget_slider widget_tab widget_table widget_text widget_tree write_sylk wtn xfont xregistered xsq_test</Keywords>
<Keywords name="Words3">annotate arrow axis bar_plot blas_axpy box_cursor breakpoint byteorder caldata calendar call_method call_procedure catch cd cir_3pnt close color_convert compile_opt constrained_min contour copy_lun cpu create_view cursor cw_animate_getp cw_animate_load cw_animate_run cw_light_editor_get cw_light_editor_set cw_palette_editor_get cw_palette_editor_set define_key define_msgblk define_msgblk_from_file defsysv delvar device dfpmin dissolve dlm_load doc_librar draw_roi efont empty enable_sysrtn erase errplot expand file_chmod file_copy file_delete file_lines file_link file_mkdir file_move file_readlink flick flow3 flush forward_function free_lun funct gamma_ct get_lun grid_input h_eq_ct h_eq_int heap_free heap_gc hls hsv icontour iimage image_cont image_statistics internal_volume iplot isocontour isosurface isurface itcurrent itdelete itgetcurrent itregister itreset ivolume journal la_choldc la_ludc la_svd la_tridc la_triql la_trired linkimage loadct ludc make_dll map_continents map_grid map_proj_info map_set mesh_obj mk_html_help modifyct mpeg_close mpeg_put mpeg_save msg_cat_close msg_cat_compile multi obj_destroy on_error on_ioerror online_help openr openw openu oplot oploterr particle_trace path_cache plot plot_3dbox plot_field ploterr plots point_lun polar_contour polyfill polywarp popd powell printf printd ps_show_fonts psafm pseudo ptr_free pushd qhull rdpix readf read_interfile read_jpeg read_pict read_ppm read_srf read_wave read_x11_bitmap reads readu reduce_colors register_cursor replicate_inplace resolve_all resolve_routine restore save scale3 scale3d set_plot set_shading setenv setup_keys shade_surf shade_surf_irr shade_volume shmmap show3 showfont skip_lun slicer3 slide_image socket spawn sph_4pnt streamline stretch strput struct_assign struct_hide surface surfr svdc swap_enian_inplace t3d tek_color threed time_test2 triangulate triql trired truncate_lun tv tvcrs tvlct tvscl usersym vector_field vel velovect voronoi wait wdelete wf_draw widget_control widget_displaycontextmenu window write_bmp write_image write_jpeg write_nrif write_pict write_png write_ppm write_spr write_srf write_tiff write_wav write_wave writeu wset wshow xbm_edit xdisplayfile xdxf xinteranimate xloadct xmanager xmng_tmpl xmtool xobjview xobjview_rotate xobjview_write_image xpalette xpcolo xplot3d xroi xsurface xvaredit xvolume xyouts zoom zoom_24</Keywords>
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