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| author | Steve Bennett <steveb@workware.net.au> | 2019-11-04 08:41:32 +1000 |
|---|---|---|
| committer | Steve Bennett <steveb@workware.net.au> | 2019-11-09 19:59:15 +1000 |
| commit | dd064e670daf910fa50e138ec0c36822405b60f5 (patch) | |
| tree | c512150b006c3e1dbc7f4575e2d744133caa0b59 /jsonencode.tcl | |
| parent | 529c84b4ee31f51925a9ac14247a94a428592c7d (diff) | |
| download | jimtcl-dd064e670daf910fa50e138ec0c36822405b60f5.zip jimtcl-dd064e670daf910fa50e138ec0c36822405b60f5.tar.gz jimtcl-dd064e670daf910fa50e138ec0c36822405b60f5.tar.bz2 | |
json: Add json encoder/decoder
Using the jsmn library for decoding.
Based on the original implementation by Svyatoslav Mishyn <juef@openmailbox.org>
Signed-off-by: Steve Bennett <steveb@workware.net.au>
Diffstat (limited to 'jsonencode.tcl')
| -rw-r--r-- | jsonencode.tcl | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/jsonencode.tcl b/jsonencode.tcl new file mode 100644 index 0000000..107ab1a --- /dev/null +++ b/jsonencode.tcl @@ -0,0 +1,100 @@ +# Implements 'json::encode' +# +# (c) 2019 Steve Bennett <steveb@workware.net.au> +# +# See LICENCE in this directory for licensing. + +# Encode Tcl objects as JSON +# dict -> object +# list -> array +# numeric -> number +# string -> string +# +# The schema provides the type information for the value. +# str = string +# num = numeric (or null) +# bool = boolean +# obj ... = object. parameters are 'name' 'subschema' where the name matches the dict. +# list ... = array. parameters are 'subschema' for the elements of the list/array. +# mixed ... = array of mixed types. parameters are types for each element of the list/array. + +# Top level JSON encoder which encodes the given +# value based on the schema +proc json::encode {value {schema str}} { + json::encode.[lindex $schema 0] $value [lrange $schema 1 end] +} + +# Encode a string +proc json::encode.str {value {dummy {}}} { + # Strictly we should be converting \x00 through \x1F to unicode escapes + # And anything outside the BMP to a UTF-16 surrogate pair + return \"[string map [list \\ \\\\ \" \\" \f \\f \n \\n / \\/ \b \\b \r \\r \t \\t] $value]\" +} + +# If no type is given, also encode as a string +proc json::encode. {args} { + tailcall json::encode.str {*}$args +} + +# Encode a number +proc json::encode.num {value {dummy {}}} { + if {$value in {Inf -Inf}} { + append value inity + } + return $value +} + +# Encode a boolean +proc json::encode.bool {value {dummy {}}} { + if {$value} { + return true + } + return false +} + +# Encode an object (dictionary) +proc json::encode.obj {obj {schema {}}} { + set result "\{" + set sep " " + foreach k [lsort [dict keys $obj]] { + if {[dict exists $schema $k]} { + set type [dict get $schema $k] + } elseif {[dict exists $schema *]} { + set type [dict get $schema *] + } else { + set type str + } + append result $sep\"$k\": + + append result [json::encode.[lindex $type 0] [dict get $obj $k] [lrange $type 1 end]] + set sep ", " + } + append result " \}" +} + +# Encode an array (list) +proc json::encode.list {list {type str}} { + set result "\[" + set sep " " + foreach l $list { + append result $sep + append result [json::encode.[lindex $type 0] $l [lrange $type 1 end]] + set sep ", " + } + append result " \]" +} + +# Encode a mixed-type array (list) +# Must be as many types as there are elements of the list +proc json::encode.mixed {list types} { + set result "\[" + set sep " " + foreach l $list type $types { + append result $sep + append result [json::encode.[lindex $type 0] $l [lrange $type 1 end]] + set sep ", " + } + append result " \]" +} + +# vim: se ts=4: |